Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2018	Oct. 23, 2018
Document Documentand Entity Information [Abstract]
Entity Registrant Name	SAFEGUARD SCIENTIFICS INC
Entity Central Index Key	0000086115
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		20,647,178
Trading Symbol	SFE

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 44,522	$ 20,751
Marketable securities	25,114	4,452
Trading securities	1,307	3,761
Prepaid expenses and other current assets	2,098	4,644
Total current assets	73,041	33,608
Property and equipment, net	1,293	1,513
Ownership interests in and advances to partner companies	103,702	134,691
Long-term restricted cash equivalents	0	6,336
Other assets	316	316
Total Assets	178,352	176,464
Current Liabilities:
Accounts payable	17	155
Accrued compensation and benefits	4,053	3,321
Accrued expenses and other current liabilities	2,213	1,851
Credit facility - current	16,433	0
Credit facility repayment feature	5,622	0
Convertible senior debentures	0	40,485
Total current liabilities	28,338	45,812
Credit facility - non-current	63,399	45,321
Other long-term liabilities	3,106	3,535
Total Liabilities	94,843	94,668
Commitments and contingencies (Note 10)
Equity:
Preferred stock, $0.10 par value; 1,000 shares authorized	0	0
Common stock, $0.10 par value; 83,333 shares authorized; 21,573 shares issued at September 30, 2018 and December 31, 2017	2,157	2,157
Additional paid-in capital	811,131	812,536
Treasury stock, at cost; 926 and 999 shares at September 30, 2018 and December 31, 2017, respectively	(15,284)	(17,308)
Accumulated deficit	(714,482)	(715,476)
Accumulated other comprehensive loss	(13)	(113)
Total Equity	83,509	81,796
Total Liabilities and Equity	$ 178,352	$ 176,464

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares shares in Thousands	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.10	$ 0.10
Preferred stock, shares authorized	1,000	1,000
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	83,333	83,333
Common stock, shares issued	21,573	21,573
Treasury stock, at cost; 926 and 999 shares at September 30, 2018 and December 31, 2017, respectively	926	999

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
General and administrative expense	$ 3,516	$ 3,758	$ 14,253	$ 13,191
Operating loss	(3,516)	(3,758)	(14,253)	(13,191)
Other loss	(1,078)	(379)	(4,965)	(219)
Interest income	718	1,004	2,182	2,892
Interest expense	(3,310)	(2,643)	(9,422)	(5,953)
Equity income (loss)	39,246	(12,874)	27,452	(53,373)
Net income (loss) before income taxes	32,060	(18,650)	994	(69,844)
Income tax benefit (expense)	0	0	0	0
Net income (loss)	$ 32,060	$ (18,650)	$ 994	$ (69,844)
Net income (loss) per share:
Basic (in dollars per share)	$ 1.56	$ (0.91)	$ 0.05	$ (3.42)
Diluted (in dollars per share)	$ 1.56	$ (0.91)	$ 0.05	$ (3.42)
Weighted average shares used in computing income (loss) per share:
Basic (in shares)	20,561	20,455	20,535	20,416
Diluted (in shares)	20,561	20,455	20,535	20,416

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows from Operating Activities:
Net cash used in operating activities	$ (18,649)	$ (15,515)
Cash Flows from Investing Activities:
Proceeds from sales of and distributions from companies	69,912	16,604
Acquisitions of ownership interests in companies	(3,250)	(11,851)
Advances and loans to companies	(12,098)	(16,933)
Repayment of advances and loans to companies	10,652	0
Purchases of marketable securities	(24,858)	0
Proceeds, from sales and maturities in marketable securities	4,211	10,268
Proceeds from sales of property and equipment	1	0
Net cash provided by (used in) investing activities	44,570	(1,912)
Cash Flows from Financing Activities:
Proceeds from credit facility	35,000	50,000
Issuance costs of credit facility	(2,252)	(5,696)
Repurchase of convertible senior debentures	(41,000)	(14,455)
Issuance of Company common stock, net	0	12
Tax withholdings related to equity-based awards	(234)	(175)
Net cash provided by (used in) financing activities	(8,486)	29,686
Net change in cash, cash equivalents and restricted cash equivalents	17,435	12,259
Cash, cash equivalents and restricted cash equivalents at beginning of period	27,087	28,394
Cash, cash equivalents and restricted cash equivalents at end of period	$ 44,522	$ 40,653

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - 9 months ended Sep. 30, 2018 - USD ($) shares in Thousands, $ in Thousands	Total	Accumulated Deficit	AOCI Attributable to Parent	Common Stock	Additional Paid-in Capital	Treasury Stock
Balance at Dec. 31, 2017	$ 81,796	$ (715,476)	$ (113)	$ 2,157	$ 812,536	$ (17,308)
Balance (in shares) at Dec. 31, 2017				21,573
Balance (in shares) at Dec. 31, 2017						999
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	994	994
Stock options exercised, net of tax withholdings	0				(16)	$ 16
Stock options exercised, net of tax withholdings (in shares)						1
Issuance of restricted stock, net of tax withholdings	(234)				(2,242)	$ 2,008
Issuance of restricted stock, net of tax withholdings (in shares)						(72)
Stock-based compensation expense	853				853
Other comprehensive income	100		100
Balance at Sep. 30, 2018	$ 83,509	$ (714,482)	$ (13)	$ 2,157	$ 811,131	$ (15,284)
Balance (in shares) at Sep. 30, 2018				21,573
Balance (in shares) at Sep. 30, 2018						926

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Statement - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 32,060	$ (18,650)	$ 994	$ (69,844)
Share of other comprehensive income of equity method investments	33	274	33	277
Reclassification adjustment for sale of equity method investments	(14)	0	67	50
Total comprehensive income (loss)	$ 32,079	$ (18,376)	$ 1,094	$ (69,517)

General

9 Months Ended

Sep. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

General

The accompanying unaudited interim Consolidated Financial Statements of Safeguard Scientifics, Inc. (“Safeguard” or the “Company”) were prepared in accordance with accounting principles generally accepted in the United States of America and the interim financial statement rules and regulations of the SEC. In the opinion of management, these statements include all adjustments (consisting only of normal recurring adjustments) necessary for a fair presentation of the Consolidated Financial Statements. The interim operating results are not necessarily indicative of the results for a full year or for any interim period. Certain information and note disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to such rules and regulations relating to interim financial statements. The Consolidated Financial Statements included in this Form 10-Q should be read in conjunction with Management’s Discussion and Analysis of Financial Condition and Results of Operations included elsewhere in this Form 10-Q and with the Company’s Consolidated Financial Statements and Notes thereto included in the Company’s 2017 Annual Report on Form 10-K.

Liquidity

As of September 30, 2018, the Company had $44.5 million of cash and cash equivalents and $25.1 million of marketable securities for a total of $69.6 million. As of September 30, 2018, the Company had $85.0 million of principal outstanding on its Amended Credit Facility (as defined below) due in May 2020. The Company currently has $15.0 million of availability under the Amended Credit Facility.

In January 2018, Safeguard announced that, from that date forward, the Company will not deploy any capital into new partner company opportunities and will focus on supporting its existing partner companies and maximizing monetization opportunities for partner company interests to enable distributions of net proceeds to shareholders. In that context, the Company will consider initiatives including, among others: the sale of individual partner companies, the sale of certain partner company interests in secondary market transactions, or a combination thereof, as well as other opportunities to maximize shareholder value. The Company anticipates distributing to shareholders net proceeds from the sale of partner companies or partner company interests, as applicable, after satisfying its debt obligations and working capital needs. In connection with the Company's change in strategy, in January 2018, the Company implemented an initiative to reduce the operating costs of the Company. In April 2018, the Company announced additional management changes intended to further streamline the Company's organizational structure and further reduce its operating costs. In connection with the changes that the Company has implemented, the Company will incur approximately $4.0 million of severance payments to terminated employees that will be paid over approximately twelve months. The Company anticipates that with these organizational changes and cost reduction initiatives, its ongoing annualized operating expenses excluding interest, depreciation, severance and stock-based compensation, will approximate $8 million to $9 million.

In May 2017, the Company entered into a $75.0 million secured, revolving credit facility (“Credit Facility”) with HPS Investment Partners, LLC (“Lender”). In May 2018, the Company and Lender amended the Credit Facility ("Amended Credit Facility") to increase the principal amount of indebtedness available to be borrowed by the Company from $75.0 million to $100.0 million. The interest rate and maturity date of May 2020 remained unchanged. The Amended Credit Facility consists of a term loan in the principal amount of $85.0 million, (the “Term Loan”), $50.0 million of which was outstanding prior to entering into the amendment and $35.0 million of which was drawn in connection with the consummation of the amendment, and a revolving loan in the principal amount of up to $15.0 million (the “Revolving Loan”). The Company may borrow and repay under the Revolving Loan at any time until its expiration on December 30, 2018. Any amounts outstanding under the Revolving Loan on December 30, 2018 will be subject to the same repayment terms as amounts borrowed under the Term Loan. Repayment terms under the Amended Credit Facility include a make-whole interest provision equal to the interest that would have been payable had the principal amount subject to repayment been outstanding through the maturity date of the Amended Credit Facility. Under the Amended Credit Facility, if the aggregate amount of the Company’s qualified cash at any quarter end date exceeds $50.0 million, the Company will be required to prepay outstanding principal amounts under the Amended Credit Facility, plus any applicable accrued and make-whole interest, in an amount equal to 100% of such excess.

Certain debt covenants were revised in connection with the Amended Credit Facility. The Amended Credit Facility requires the Company to (i) maintain a liquidity threshold of at least $20 million of unrestricted cash; (ii) maintain a minimum aggregate appraised value of the Company’s ownership interests in its partner companies, plus unrestricted cash in excess of the liquidity threshold, of at least $350 million less the aggregate amount of all prepayments of the Term Loan and all prepayments of the Revolving Loan made after December 30, 2018; (iii) limit deployments to only existing partner companies and such deployments may not exceed, when combined with deployments after January 1, 2018, $40.0 million in the aggregate through the maturity date; and (iv) limit certain expenses (which shall exclude severance payments, interest expense, depreciation and stock-based compensation) incurred or paid to no more than $11.5 million in any twelve-month period after the date of the amendment (or such shorter period as has elapsed since the date of the amendment). The Company is no longer required to maintain a specific net worth or any diversification requirements or concentration limits with respect to the Company’s capital deployments to its partner companies. Additionally, under the Amended Credit Facility, the Company is restricted from repurchasing shares of its outstanding common stock and/or issuing dividends until such time as the Amended Credit Facility is repaid in full. As of the date these consolidated financial statements were issued, the Company was in compliance with all applicable covenants.

The $35.0 million of additional principal that the Company borrowed with the consummation of the Amended Credit Facility resulted in net proceeds of $32.7 million, after closing fees to the Lender and other third parties, that were used towards the repayment of $41.0 million of principal outstanding on its 2018 Debentures, which the Company repaid in full on the maturity date of May 15, 2018. There were no convertible debentures outstanding as of September 30, 2018.

The Company funds its operations with cash and marketable securities on hand as well as proceeds from the sales of its interests in its partner companies. Due to the nature of the mergers and acquisitions market, and the developmental cycle of companies like the Company's partner companies, the Company's ability to generate specific amounts of liquidity from sales of its partner company interests in any given period of time cannot be assured. Accordingly, the forecasts which the Company utilizes for projecting future compliance with covenants related to its Amended Credit Facility include significantly discounted probability-weighted proceeds from the sales of its interests in its partner companies. Based on these forecasts, management believes the Company will remain in compliance with all its debt covenants. Non-compliance with any of the covenants would constitute an event of default under the Amended Credit Facility, and the Lender could choose to accelerate the maturity of the indebtedness. If the Lender chose not to provide a waiver and were to accelerate the maturity of the indebtedness, the Company may not have sufficient liquidity to repay the entire balance of its outstanding borrowings and other obligations under the Amended Credit Facility.

In order for the Company to maintain compliance with these covenants, the Company's plan includes selling certain of its partner company interests in the ordinary course of its business and limiting capital deployments to existing partner companies, if necessary. Should the Company not be in compliance with any of its debt covenants and be unable to obtain waivers for such events of default, management would pursue one of a number of potential alternatives to satisfy the obligations, including completing an equity offering or obtaining a new debt facility to refinance its existing debt. The Company believes that its cash, cash equivalents and marketable securities at September 30, 2018 will be sufficient to fund operations past one year from the issuance of these financial statements.

Significant Accounting Policies

Restricted Cash Equivalents

Restricted cash equivalents in prior periods represented cash required to be set aside by a contractual agreement with a bank as collateral for a letter of credit. During the first quarter of 2018, the restriction on the cash lapsed in connection with the termination of the related letter of credit. The following table provides a reconciliation of cash, cash equivalents and restricted cash equivalents reported within the Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows:



	September 30, 2018		December 31, 2017
	(Unaudited - In thousands)
Cash and cash equivalents	$	44,522	$	20,751
Long-term restricted cash equivalents	—		6,336
Total cash, cash equivalents and restricted cash equivalents	$	44,522	$	27,087

Recently Adopted Accounting Pronouncements

In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities. ASU 2016-01 requires that equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) are to be measured at fair value with changes in fair value recognized in net income. However, an entity may choose to measure equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Furthermore, equity investments without readily determinable fair values are to be assessed for impairment using a qualitative approach. The amendments in ASU 2016-01 should be applied by means of a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption, with other amendments related specifically to equity securities without readily determinable fair values applied prospectively. The Company adopted the amendments in ASU 2016-01 when they became effective on January 1, 2018. The adoption of this guidance did not have a material impact upon the Company's financial condition or results of operations.

In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASU 2014-09"). ASU 2014-09 and related subsequent amendments outline a single comprehensive model to use to account for revenue arising from contracts with customers and supersede most current revenue recognition guidance. For public companies, the guidance is effective for annual periods beginning after December 15, 2017 and any interim periods that fall within that reporting period. For nonpublic companies, the guidance is effective for annual periods beginning after December 15, 2018 and interim periods within annual periods beginning after December 15, 2019 with early adoption permitted. As the new standard will supersede most existing revenue guidance, it could impact revenue and cost recognition for partner companies. Any change in revenue or cost recognition for partner companies could affect the Company's recognition of its share of the results of its equity method partner companies. On July 20, 2017, the SEC staff observer at the FASB’s Emerging Issues Task Force ("EITF") meeting announced that the SEC staff will not object if a private company equity method investee meeting the definition of a public business entity that otherwise would not meet the definition of a public business entity except for the inclusion of its financial statements or financial information in another entity’s filings with the SEC, uses private company adoption dates for the new revenue standard. As a result, the Company's private, calendar year partner companies will adopt the new revenue standard for the year ending December 31, 2019. The impact of adoption of the new revenue standard will be reflected in the Company’s financial results for the interim and annual reporting periods beginning in 2020 on a one quarter-lag basis.

Recently Issued Accounting Pronouncements Not Yet Adopted

In February 2016, the FASB issued ASU 2016-02, Leases. The guidance in ASU 2016-02 requires that a lessee recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. As with previous guidance, there continues to be a differentiation between finance leases and operating leases, however this distinction now primarily relates to differences in the manner of expense recognition over time and in the classification of lease payments in the statement of cash flows. Lease assets and liabilities arising from both finance and operating leases will be recognized in the statement of financial position. The transitional guidance for adopting the requirements of ASU 2016-02 calls for a modified retrospective approach that includes a number of optional practical expedients that entities may elect to apply. The guidance in ASU 2016-02 will become effective for the Company on January 1, 2019. The Company anticipates making the accounting policy election not to recognize lease assets and lease liabilities for leases with a term of 12 months or less. As of September 30, 2018, the Company's only material long-term lease was for its corporate headquarters in Radnor, PA under a lease expiring in 2026. The Company also has immaterial office equipment leases expiring at various dates through 2020. The Company is currently evaluating the impact that the adoption of ASU 2016-02 will have on its consolidated financial statements.

Ownership Interests in and Advances to Partner Companies and Funds

9 Months Ended

Sep. 30, 2018

Investments in and Advances to Affiliates, Schedule of Investments [Abstract]

Ownership Interests in and Advances to Partner Companies

The following summarizes the carrying value of the Company’s ownership interests in and advances to partner companies.



	September 30, 2018		December 31, 2017
	(Unaudited - In thousands)
Equity Method Companies:
Partner companies	$	71,248	$	107,646
Private equity funds	440		443
	71,688		108,089
Other Companies:
Partner companies and other holdings	15,260		2,762
Private equity funds	1,311		1,334
	16,571		4,096
Advances to partner companies	15,443		22,506
	$	103,702	$	134,691

The Company recognized an impairment charge of it's entire carrying value of $4.8 million related to CloudMine, Inc. which is reflected in Equity income (loss) in the Consolidated Statements of Operations for the three and nine months ended September 30, 2018. The impairment results from our inability to recover the carrying value of the investment as the company has not identified new investors.

In July 2018, the Company sold 39.13% of its ownership position in MediaMath back to MediaMath for $45.0 million. The Company also granted MediaMath an option to repurchase an additional 10.87% of the Company’s ownership position in MediaMath for $12.5 million within 180 days after the close of the initial transaction. The Company recognized a gain of $45.0 million on the initial transaction, which was included in Equity income (loss) in the Consolidated Statements of Operations for the three and nine months ended September 30, 2018. The Company previously accounted for its ownership interest in MediaMath under the equity method of accounting. Immediately after the initial transaction, the Company discontinued utilizing the equity method of accounting for its remaining ownership interest in MediaMath. The Company's remaining ownership interest was recorded at its carrying value immediately prior to the initial transaction. The carrying value will be adjusted for any future impairments or observable price changes in the same or similar equity securities of MediaMath as those held by the Company.

In July 2018, the Company sold its interest in AdvantEdge Healthcare Solutions, Inc. in a secondary transaction for $10.0 million, excluding an additional $6.3 million that may be realized upon the achievement of certain valuation thresholds in connection with the future sale of Advantage Healthcare Solutions. The Company recognized a gain of $5.5 million on the transaction, which was included in Equity income (loss) in the Consolidated Statements of Operations for the three and nine months ended September 30, 2018.

In May 2018, Cask Data, Inc. sold substantially all of its assets to another entity. The Company received $11.5 million in cash proceeds in connection with the transaction, excluding $2.4 million of holdbacks and escrows that may be released on various dates on or before November 2019. The Company recognized a gain of $4.2 million on the transaction, which was included in Equity income (loss) in the Consolidated Statements of Operations for the three and nine months ended September 30, 2018.

The Company recognized an impairment charge of $6.6 million related to Apprenda, Inc. which is reflected in Equity income (loss) in the Consolidated Statements of Operations for the nine months ended September 30, 2018. The impairment was based on Apprenda's decision to discontinue operations. The adjusted carrying value of the Company's interest in Apprenda was $0.0 million at September 30, 2018.

In February 2018, Nexxt, Inc., formerly Beyond.com, repaid $10.5 million of principal outstanding on a note received in connection with the Company's sale of its interest back to Nexxt for $26.0 million in March 2017. In that transaction, the Company received $15.5 million in cash and a three-year, $10.5 million note for the balance due, which accrued interest at a rate of 9.5% per annum. Interest was payable annually and interest income was recorded as earned throughout the year. The $10.5 million note was fully reserved and had a carrying value of zero as of December 31, 2017. The Company waived the interest accrued to date in connection with the early repayment of the principal balance. The receipt of $10.5 million of cash in February 2018 resulted in a gain of $9.5 million, net of the interest accrued to date, which is included in Equity income (loss) in the Consolidated Statements of Operations for the nine months ended September 30, 2018.

In January 2018, Spongecell, Inc. merged into Flashtalking, a privately-held company. The Company received Flashtalking ordinary shares equal to approximately 10% of Flashtalking’s issued share capital at the time of the closing. The Company’s final number of Flashtalking shares will be subject to customary indemnification and working capital provisions and agreements. The Company recorded its ownership interest in Flashtalking at $11.2 million, which reflects its fair value at the time of closing. The Company recognized a gain of $3.9 million on the transaction, which is included in Equity income (loss) in the Consolidated Statements of Operations for the nine months ended September 30, 2018.

In February 2018, the Company sold 414,237 shares of Invitae Corporation ("Invitae") common stock on the open market for proceeds of $2.6 million after transaction fees. The Company obtained shares of Invitae in August 2017 when Invitae, a public company, acquired former partner company Good Start Genetics, Inc. In that transaction, the Company received 414,237 shares of Invitae common stock, excluding 124,092 shares of Invitae common stock which will be held in escrow. During the third quarter, 78,103 additional shares were released from escrow and recorded as an additional gain of $1.1 million from this transaction, which is included in Equity income (loss) in the Consolidated Statements of Operations for the three and nine months ended September 30, 2018. The Invitae shares were classified as Trading securities and recorded at their fair value, which was $1.3 million and $3.8 million at September 30, 2018 and December 31, 2017, respectively. For the three and nine months ended September 30, 2018, the Company recorded a $0.2 million gain and a $1.0 million net loss, respectively, due to a change in the value of the Invitae shares, which is included in Other loss in the Consolidated Statements of Operations.

In January 2018, the Company received $0.6 million of proceeds from the sale of the assets of Aventura, Inc., a former partner company that ceased operations and was fully impaired in 2016. The Company recognized a gain of $0.6 million, which is reflected in Equity income (loss) in the Consolidated Statements of Operations for the nine months ended September 30, 2018.

Summarized Financial Information

The Company discloses aggregate summarized statements of operations for any partner companies accounted for under the equity method that are deemed significant. The following table provides significant partner company operations information for the three and nine months ended September 30, 2018. The partner company results of operations have been compiled from respective partner company financial statements, reflect certain historical adjustments, and are reported on a one quarter lag basis. Results of operations of the partner companies are excluded for periods prior to their acquisition, subsequent to their disposition and subsequent to the discontinuation of equity method of accounting. Historical results are not adjusted when the Company exits, writes-off or discontinues the equity method of accounting for a partner company.



	Three months ended September 30,						Nine months ended September 30,
	2018			2017			2018			2017
	(Unaudited - In thousands)
Results of Operations:
Revenue	$	40,070		$	91,137		$	234,049		$	275,154
Gross profit	$	21,822		$	60,836		$	153,387		$	180,158
Net loss	$	(34,885	)	$	(52,648	)	$	(120,971	)	$	(148,439	)

Acquisitions of Ownership Interests in Partner Companies and Funds	9 Months Ended
	Sep. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Acquisitions of Ownership Interests in Partner Companies	Acquisitions of Ownership Interests in Partner Companies Third quarter of 2018 The Company funded an aggregate of $0.7 million of term notes to InfoBionic, Inc. The Company had previously deployed an aggregate of $21.3 million in InfoBionic. InfoBionic is an emerging digital health company focused on creating patient monitoring solutions for chronic disease management with an initial market focus on cardiac arrhythmias. The Company accounts for its interest in InfoBionic under the equity method. The Company deployed an additional $1.0 million in meQuilibrium. The Company had previously deployed and aggregate of $10.5 million in meQuilibrium. meQuilibrium is a digital coaching platform that delivers clinically validated and highly personalized resilience solutions to employers, health plans, wellness providers and consumers increasing engagement, productivity and performance, as well as improving outcomes in managing stress, health and well-being. The Company accounts for its interest in meQuilibrium under the equity method. The Company funded an additional $1.0 million of convertible bridge loans to Moxe Health Corporation. The Company had previously deployed $4.5 million in Moxe Health. Moxe Health connects payers to their provider networks, facilitating real-time data exchange through its electronic integration platform. The Company accounts for its interest in Moxe Health under the equity method. The Company funded an additional $1.5 million in Zipnosis, Inc. The Company had previously deployed $7.0 million in Zipnosis. Zipnosis provides health systems with a white-labeled, fully integrated virtual care platform. The Company accounts for its interest in Zipnosis under the equity method. The Company deployed an aggregate of $0.4 million of convertible bridge loans to CloudMine, Inc. The Company had previously deployed an aggregate of $10.5 million in CloudMine. CloudMine empowers healthcare organizations to rapidly and confidently develop connected digital health experiences by reducing complexity, enabling data mobility, and ensuring compliance. The Company accounts for its interest in CloudMine under the equity method. The Company funded an additional $0.5 million in Aktana, Inc. The Company had previously deployed $9.7 million in Aktana. Aktana leverages big data and machine learning to enable pharmaceutical brands to dynamically optimize their strategy and enhance sales execution. The Company accounts for its interest in Aktana under the equity method. The Company funded an additional $1.4 million of convertible bridge loans to QuanticMind, Inc. The Company had previously deployed $11.5 million in QuanticMind. QuanticMind delivers the most intelligent, scalable and fastest platform for maximizing digital marketing performance, including paid search and social, for enterprises. The Company accounts for its interest in QuanticMind under the equity method. The Company funded an additional $0.5 million of convertible bridge loans to Sonobi, Inc. The Company had previously deployed $10.9 million in Sonobi. Sonobi is an advertising technology developer that designs advertising tools and solutions for the industry's leading media, publishers, brand advertisers, media agencies, DSPs, and media technology providers. The Company accounts for its interest in Sonobi under the equity method. Second quarter of 2018 The Company funded an aggregate of $1.5 million of a convertible bridge loan to Sonobi, Inc. The Company funded an aggregate of $0.8 million of convertible bridge loans to InfoBionic, Inc. The Company deployed an aggregate of $0.5 million of convertible bridge loans to CloudMine, Inc. The Company funded an aggregate of $0.2 million of convertible bridge loans to WebLinc, Inc. The Company had previously deployed an aggregate of $14.5 million in WebLinc. WebLinc is an e-commerce platform and services provider for fast growing online retailers. The Company accounts for its interest in WebLinc under the equity method. The Company deployed an additional $0.3 million in Propeller Health, Inc. The Company had previously deployed an aggregate of $14.0 million in Propeller Health. Propeller Health provides digital solutions to measurably improve respiratory health. The Company accounts for its interest in Propeller Health under the equity method. The Company funded an aggregate of $0.2 million of convertible bridge loans to Cask Data, Inc. The Company had previously deployed an aggregate of $13.3 million in Cask Data. Cask Data made building and running big data solutions on-premises or in the cloud easy with Cask Data Application Platform. In May 2018, Cask Data sold substantially all of its assets to another entity. The Company had previously accounted for its interest in Cask Data under the equity method. The Company funded an aggregate of $0.8 million of convertible loans to NovaSom, Inc. The Company had previously deployed an aggregate of $25.4 million in NovaSom. NovaSom is a medical device company focused on obstructive sleep apnea, specifically home testing with its FDA-cleared wireless device called AccuSom^® home sleep test. The Company accounts for its interest in NovaSom under the equity method. First quarter of 2018 The Company funded an aggregate of $1.3 million of convertible loans to NovaSom, Inc. The Company funded an aggregate of $0.8 million of convertible bridge loans to InfoBionic, Inc. The Company funded an aggregate of $0.5 million of convertible bridge loans to Spongecell, Inc. The Company had previously deployed an aggregate of $18.6 million in Spongecell. In the first quarter of 2018, Spongecell merged into Flashtalking. The Company previously accounted for its interest in Spongecell under the equity method. The Company funded an aggregate of $0.5 million of convertible bridge loans to WebLinc, Inc. The Company funded an aggregate of $0.4 million of convertible bridge loans to Brickwork. The Company had previously deployed an aggregate of $4.2 million in Brickwork. Brickwork helps retailers inform, target, convert, and prepare for store shoppers online as the first scalable software-as-a-service platform powering a seamless customer path between online and in-store shopping. The Company accounts for its interest in Brickwork under the equity method. The Company funded an aggregate of $0.3 million of convertible bridge loans to Cask Data, Inc. The Company funded an aggregate of $0.2 million of a convertible bridge loan to Sonobi, Inc.

Fair Value Measurements

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company categorizes its financial instruments into a three-level fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). If the inputs used to measure fair value fall within different levels of the hierarchy, the category level is based on the lowest priority level input that is significant to the fair value measurement of the instrument. Financial instruments recorded at fair value on the Company’s Consolidated Balance Sheets are categorized as follows:

Level 1—Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.

Level 2—Include other inputs that are directly or indirectly observable in the marketplace.

Level 3—Unobservable inputs which are supported by little or no market activity.

The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value.

The following table provides the carrying value and fair value of certain financial assets and liabilities of the Company measured at fair value on a recurring basis as of September 30, 2018 and December 31, 2017:



	Carrying Value		Fair Value Measurement at September 30, 2018
	Carrying Value		Level 1		Level 2		Level 3
	(Unaudited - In thousands)
Cash and cash equivalents	$	44,522	$	44,522	$	—	$	—
Trading securities	1,307		1,307		—		—
Marketable securities—held-to-maturity:
Certificates of deposit	249		—		249		—
Government agency bond	$	8,471	$	8,471	$	—	$	—
U.S. Treasury Bills	$	16,394	$	16,394	$	—	$	—
Total marketable securities	$	25,114	$	24,865	$	249	$	—

Credit facility repayment feature liability	$	5,622	$	—	$	—	$	5,622



	Carrying Value		Fair Value Measurement at December 31, 2017
	Carrying Value		Level 1		Level 2		Level 3
	(Unaudited - In thousands)
Cash and cash equivalents	$	20,751	$	20,751	$	—	$	—
Long-term restricted cash equivalents	6,336		6,336		—		—
Trading securities	3,761		3,761		—		—
Marketable securities—held-to-maturity:
Certificates of deposit	$	4,452	$	4,452	$	—	$	—

As of September 30, 2018, $25.1 million of marketable securities had contractual maturities which were less than one year. Held-to-maturity securities are carried at amortized cost, which, due to the short-term maturity of these instruments, approximates fair value using quoted prices in active markets for identical assets or liabilities defined as Level 1 inputs under the fair value hierarchy. As of September 30, 2018, $5.6 million is recorded as a credit facility repayment feature liability, an increase of $2.6 million from June 30, 2018, due to the provision in the Amended Credit Facility that requires prepayments of outstanding principal amounts when the Company’s qualified cash at any quarter end date exceeds $50.0 million. The prepayment feature is an embedded derivative that is accounted for as a liability separate from the Amended Credit Facility. The liability is adjusted to the fair value of potential future debt prepayments based upon management's probability weighted cash forecast at each balance sheet date. Management's cash forecasts are defined as Level 3 inputs under the fair value hierarchy.

Trading securities as of September 30, 2018 consisted of 78,103 shares of Invitae Corporation common shares released from escrow during the third quarter in connection with the sale of Good Start Genetics. Trading securities at December 31, 2017 consisted of 414,237 shares of Invitae Corporation common shares obtained in connection with the sale of Good Start Genetics. The trading securities were carried at fair value based on the closing stock price on the last trading day of the reporting period. The Company sold all of the initial Invitae shares that we held as of December 31, 2017 during the first quarter of 2018 for $2.6 million of cash proceeds.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Credit Facility and Convertible Debentures	9 Months Ended
Credit Facility and Convertible Debentures	Sep. 30, 2018
Debt Disclosure [Abstract]
Credit Facility and Convertible Debentures	Credit Facility and Convertible Debentures Credit Facility In May 2017, the Company entered into a $75.0 million secured, revolving credit facility (“Credit Facility”) with HPS Investment Partners, LLC (“Lender”). At closing, the Company borrowed $50.0 million, which resulted in net proceeds of $44.3 million after closing fees to the Lender and other third parties. The Credit Facility has a three-year term with a scheduled maturity of May 11, 2020 and bears interest at a rate of either: (A) LIBOR plus 8.5% (subject to a LIBOR floor of 1%), payable on the last day of the one, two or three month interest period applicable to the LIBOR rate advance, or (B) 7.5% plus the greater of: 2%; the Federal Funds Rate plus 0.5%; LIBOR plus 1%; or the U.S. Prime Rate, payable monthly in arrears. The Credit Facility is not amortized and interest payable under the Credit Facility reflects at least $50 million as being drawn and outstanding at all times during the term. The Credit Facility also included an unused line fee equal to 0.75% per annum of the average unused portion of the Credit Facility and a loan service fee, both paid quarterly. The Credit Facility is secured by all of the Company's assets in accordance with the terms of the Credit Facility. In May 2018, the Company and Lender amended the Credit Facility ("Amended Credit Facility") to increase the principal amount of indebtedness available to be borrowed by the Company from $75.0 million to $100.0 million. The maturity date and interest rate remained unchanged. The Amended Credit Facility consists of a term loan in the principal amount of $85.0 million, (the “Term Loan”), $50.0 million of which was outstanding prior to entering into the amendment and $35.0 million of which was drawn in connection with the consummation of the amendment, and a revolving loan in the principal amount of up to $15.0 million (the “Revolving Loan”). The Company may borrow and repay under the Revolving Loan at any time until its expiration on December 30, 2018. Any amounts outstanding under the Revolving Loan on December 30, 2018 will be subject to the same repayment terms as amounts borrowed under the Term Loan. Repayment terms under the Credit Facility include a make-whole interest provision equal to the interest that would have been payable had the principal amount subject to repayment been outstanding through the maturity date of the Credit Facility. Under the Amended Credit Facility, if the aggregate amount of the Company’s qualified cash at any quarter end date exceeds $50.0 million, the Company will be required to prepay outstanding principal amounts under the Amended Credit Facility, plus any applicable interest and prepayment fees, in an amount equal to 100% of such excess. Based on this requirement, the Company made a principal payment of $16.4 million and a make-whole interest payment of $2.8 million on October 15, 2018 based on the Company's qualified cash at September 30, 2018. Certain debt covenants were revised in connection with the Amended Credit Facility. The Amended Credit Facility requires the Company to (i) maintain a liquidity threshold of at least $20 million of unrestricted cash; (ii) maintain a minimum aggregate appraised value of the Company’s ownership interests in its partner companies, plus unrestricted cash in excess of the liquidity threshold, of at least $350 million less the aggregate amount of all prepayments of the Term Loan and all prepayments of the Revolving Loan made after December 30, 2018; (iii) limit deployments to only existing partner companies and such deployments may not exceed, when combined with deployments after January 1, 2018, $40.0 million in the aggregate through the maturity date; and (iv) limit certain expenses (which shall exclude severance payments, interest expense, depreciation and stock-based compensation) incurred or paid to no more than $11.5 million in any twelve-month period after the date of the amendment (or such shorter period as has elapsed since the date of the amendment). The Company is no longer required to maintain a specific net worth or any diversification requirements or concentration limits with respect to the Company’s capital deployments to its partner companies. Additionally, under the Amended Credit Facility, the Company is restricted from repurchasing shares of its outstanding common stock and/or issuing dividends until such time as the Amended Credit Facility is repaid in full. As of the date these consolidated financial statements were issued, the Company was in compliance with all applicable covenants. The $35.0 million of additional principal that the Company borrowed with the consummation of the Amended Credit Facility resulted in net proceeds of $32.7 million, after closing fees to the Lender and other third parties, that were used towards the repayment of $41.0 million of principal outstanding on its 2018 Debentures, which the Company repaid in full on the maturity date of May 15, 2018. There were no convertible debentures outstanding as of September 30, 2018. The Amended Credit Facility provides for customary events of default which include (subject in certain cases to customary grace and cure periods), among others, nonpayment of principal or interest; non-compliance with debt covenants; defaults in, or failure to pay, certain other indebtedness; the rendering of judgments to pay certain amounts of money; and certain events of bankruptcy or insolvency. Generally, if an event of default occurs and is not cured within the time periods specified (if any), the Lender may declare the outstanding amount under the Amended Credit Facility to be immediately due and payable. At September 30, 2018, the principal amount outstanding under the Amended Credit Facility was $85.0 million, the unamortized discount and debt issuance costs were $5.2 million and the net carrying value of the credit facility was $79.8 million. The Company accounted for the amendment to the Credit Facility as an insubstantial modification and is amortizing the excess of the principal amount of the Amended Credit Facility over its carrying value over the remaining term as additional interest expense using a revised effective interest rate prospectively based on the revised cash flows. The Amended Credit Facility requires prepayments of outstanding principal amounts when the Company’s qualified cash at any quarter end date exceeds $50.0 million. This provision in the Amended Credit Facility is an embedded derivative that is accounted for separately from the credit facility. A liability of $0.5 million was recorded on the amendment date for the fair value of potential future prepayments based upon management's probability weighted cash forecast. This amount is also included in debt issuance costs and will be amortized over the remaining term of the credit facility. The liability will be adjusted to fair value at each balance sheet date based upon management's updated probability weighted cash forecast. During the three and nine months ended September 30, 2018, the Company recorded losses of $2.6 million and $5.1 million, respectively, which is included in Other loss on the Consolidated Statements of Operations. The losses mainly relate to an increase in the fair value of the credit facility repayment feature liability due to an increase in the probability of debt prepayments caused by $55.0 million of proceeds received in July 2018 in connection with the MediaMath and AdvantEdge Healthcare Solutions transactions. The Company recorded interest expense of $3.3 million and $1.7 million for the three months ended September 30, 2018 and 2017, respectively, and $8.0 million and $2.6 million for the nine months ended September 30, 2018 and 2017, respectively, under the Amended Credit Facility. The effective interest rate on the Amended Credit Facility is 14.9%. The Company made interest payments of $2.4 million and $1.2 million for the three months ended September 30, 2018 and 2017, respectively, and $4.9 million and $1.2 million for the nine months ended September 30, 2018 and 2017, respectively. Convertible Debentures In November 2012, the Company issued $55.0 million principal amount of its 5.25% convertible senior debentures due on May 15, 2018 (the “2018 Debentures”). Interest on the 2018 Debentures was payable semi-annually. In July and June 2017, the Company repurchased on the open market, and retired, an aggregate of $14.0 million face value of the 2018 Debentures at a cost of $14.5 million, including transaction fees. The Company repaid the remaining $41.0 million of principal outstanding on its 2018 Debentures in full on the maturity date of May 15, 2018. The Company had no convertible debentures outstanding as of September 30, 2018. The Company had been amortizing the excess of the face value of the 2018 Debentures over their carrying value over their term as additional interest expense using the effective interest method and the Company recorded $0.0 million and $0.9 million of interest expense for the three months ended September 30, 2018 and 2017, respectively, and $1.3 million and $3.2 million for the nine months ended September 30, 2018 and 2017, respectively. The effective interest rate on the 2018 Debentures was 8.7%. The Company made no interest payments for the three months ended September 30, 2018 and 2017 and $1.1 million and $1.5 million for the nine months September 30, 2018 and 2017, respectively.

Stock-Based Compensation

9 Months Ended

Sep. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

Stock-based compensation expense was recognized in the Consolidated Statements of Operations as follows:



	Three months ended September 30,				Nine months ended September 30,
	2018		2017		2018		2017
	(Unaudited - In thousands)
General and administrative expense	$	243	$	560	$	853	$	806
	$	243	$	560	$	853	$	806

The fair value of the Company’s option awards to employees was estimated at the date of grant using the Black-Scholes option-pricing model. The risk-free rate was based on the U.S. Treasury yield curve in effect at the end of the quarter in which the grant occurred. The expected term of stock options granted was estimated using the historical exercise behavior of employees. Expected volatility was based on historical volatility measured using weekly price observations of the Company’s common stock for a period equal to the stock option’s expected term.

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s consolidated income tax benefit (expense) was $0.0 million for the three and nine months ended September 30, 2018 and 2017. The Company has recorded a valuation allowance to reduce its net deferred tax asset to an amount that is more likely than not to be realized in future years. Accordingly, the benefit of the net operating loss that would have been recognized in the three and nine months ended September 30, 2018 was offset by changes in the valuation allowance. The tax expense that would have been recognized in the three and nine months ended September 30, 2018 was offset by changes in the valuation allowance. During the three and nine months ended September 30, 2018, the Company had no material changes in uncertain tax positions. In December 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act (the "Tax Act"). The Tax Act makes broad and complex changes to the U.S. tax code, including, but not limited to: (i) reducing the U.S. federal corporate tax rate from 35 percent to 21 percent; (ii) eliminating the corporate alternative minimum tax (AMT) and changing how existing AMT credits can be realized; (iii) creating a new limitation on deductible interest expense; and (iv) changing rules related to uses and limitations of net operating carryforwards created in tax years beginning after December 31, 2017. The most significant impact on the Company's consolidated financial statements was a reduction of approximately $82.5 million in deferred tax assets in 2017 which was offset by changes to the Company’s valuation allowance.

Net Income (Loss) Per Share

9 Months Ended

Sep. 30, 2018

Earnings Per Share [Abstract]

Net Income (Loss) Per Share

The calculations of net income (loss) per share were as follows:



	Three months ended September 30,					Nine months ended September 30,
	2018		2017			2018		2017
	(Unaudited - In thousands, except per share data)
Basic:
Net income (loss)	$	32,060	$	(18,650	)	$	994	$	(69,844	)
Weighted average common shares outstanding	20,561		20,455			20,535		20,416
Net income (loss) per share	$	1.56	$	(0.91	)	$	0.05	$	(3.42	)

Diluted:
Net income (loss) for dilutive share computation	$	32,060	$	(18,650	)	$	994	$	(69,844	)

Number of shares used in basic per share computation	20,561		20,455			20,535		20,416
Unvested restricted stock and DSU's	—		—			—		—
Employee stock options	—		—			—		—
Weighted average common shares outstanding	20,561		20,455			20,535		20,416

Net income (loss) for dilutive share computation	$	1.56	$	(0.91	)	$	0.05	$	(3.42	)

Basic and diluted average common shares outstanding for purposes of computing net income (loss) per share includes outstanding common shares and vested deferred stock units (DSUs).

If a consolidated or equity method partner company has dilutive stock options, unvested restricted stock, DSUs or warrants, diluted net income (loss) per share is computed by first deducting the income attributable to the potential exercise of the dilutive securities of the partner company from net income (loss). Any impact is shown as an adjustment to net income (loss) for purposes of calculating diluted net income (loss) per share.

Diluted earnings per share for the three and nine months ended September 30, 2018 and 2017 do not reflect the following potential shares of common stock that would have an anti-dilutive effect or have unsatisfied performance or market conditions:


•	At September 30, 2018 and 2017, options to purchase 0.4 million and 0.6 million shares of common stock, respectively, at prices ranging from $9.83 to $19.95 for both periods, were excluded from the calculations.


•	At September 30, 2018 and 2017, unvested restricted stock, performance-based stock units and DSUs convertible into 0.8 million and 0.9 million shares of stock, respectively, were excluded from the calculations.


•	1.1 million and 2.3 million shares of common stock that were outstanding during the period of 2018 and 2017, respectively, representing the effect of the assumed conversion of the 2018 Debentures, were excluded from the calculations.

Segment Reporting

9 Months Ended

Sep. 30, 2018

Segment Reporting [Abstract]

Segment Reporting

The Company operates as one operating segment based upon the similar nature of its technology-driven partner companies, the functional alignment of the organizational structure, and the reports that are regularly reviewed by the chief operating decision maker for the purpose of assessing performance and allocating resources. As of September 30, 2018, the Company held interests in 22 non-consolidated partner companies. The Company’s active partner companies were as follows as of September 30, 2018:



Partner Company	Safeguard Primary Ownership as of September 30, 2018	Accounting Method
Aktana, Inc.	20.1%	Equity
Brickwork	20.3%	Equity
CloudMine, Inc.	47.3%	Equity
Clutch Holdings, Inc.	41.2%	Equity
Flashtalking ¹	10.3%	Other
Hoopla Software, Inc.	25.5%	Equity
InfoBionic, Inc.	25.4%	Equity
Lumesis, Inc.	43.8%	Equity
MediaMath, Inc.²	13.3%	Other
meQuilibrium	33.1%	Equity
Moxe Health Corporation	32.4%	Equity
NovaSom, Inc.	31.7%	Equity
Prognos (fka Medivo, Inc.)	28.7%	Equity
Propeller Health, Inc.	19.6%	Equity
QuanticMind, Inc.	24.7%	Equity
Sonobi, Inc.	21.6%	Equity
Syapse, Inc.	20.0%	Equity
T-REX Group, Inc.	21.1%	Equity
Transactis, Inc.	23.7%	Equity
Trice Medical, Inc.	23.4%	Equity
WebLinc, Inc.	37.9%	Equity
Zipnosis, Inc.	34.7%	Equity

¹Spongecell, Inc. merged into Flashtalking in January 2018.

²The Company sold 39.1% of its ownership interest in MediaMath, Inc. back to the company for $45.0 million of proceeds in July 2018.

As of September 30, 2018 and December 31, 2017, all of the Company’s assets were located in the United States.

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company and its partner companies are involved in various claims and legal actions arising in the ordinary course of business. In the current opinion of the Company, the ultimate disposition of these matters will not have a material adverse effect on the Company’s consolidated financial position or results of operations, however, no assurance can be given as to the outcome of these actions, and one or more adverse rulings could have a material adverse effect on the Company’s consolidated financial position and results of operations or that of its partner companies. The Company records costs associated with legal fees as such services are rendered. The Company had outstanding guarantees of $3.8 million at September 30, 2018 which related to one of the Company's private equity holdings. The Company is required to return a portion or all the distributions it received as a general partner of a private equity fund for further distribution to such fund's limited partners (“clawback”). The Company’s ownership in the fund is 19%. The clawback liability is joint and several, such that the Company may be required to fund the clawback for other general partners should they default. The Company believes its potential liability due to the possibility of default by other general partners is remote. In 2017, the Company was notified by the fund's manager that the fund was being dissolved and $1.0 million of the Company's clawback liability was paid. The maximum additional clawback liability is $0.3 million which was reflected in Other long-term liabilities on the Consolidated Balance Sheet at September 30, 2018. In October 2001, the Company entered into an agreement with a former Chairman and Chief Executive Officer of the Company, to provide for annual payments of $0.65 million per year and certain health care and other benefits for life. The related current liability of $0.8 million was included in Accrued expenses and other current liabilities and the long-term portion of $1.4 million was included in Other long-term liabilities on the Consolidated Balance Sheet at September 30, 2018. The Company previously provided a $6.3 million letter of credit to the landlord of CompuCom Systems, Inc.’s Dallas headquarters as required in connection with the sale of CompuCom Systems in 2004. The letter of credit was secured by cash and was classified as Long-term restricted cash equivalents on the Consolidated Balance Sheet as of December 31, 2017. During the first quarter of 2018, the restriction on the cash lapsed in connection with the termination of the related letter of credit. In January 2018, the Company announced a change in strategy and implemented an initiative to reduce the operating costs of the Company. In April 2018, the Company announced additional management changes intended to further streamline the Company's organizational structure and further reduce its operating costs. In connection with the changes that the Company has implemented, the Company will incur approximately $4.0 million of severance payments to terminated employees that will be paid during 2018 and 2019 and is being expensed over the remaining requisite service period. The Company recognized $1.0 million and $3.8 million of severance expense for the three and nine months ended September 30, 2018, respectively, which is included in General and Administrative expenses in the Consolidated Statement of Operations. The Company made severance payments of $1.0 million and $1.5 million for the three and nine months ended September 30, 2018, respectively, and $2.3 million was classified as accrued compensation and benefits on the Consolidated Balance Sheet as of September 30, 2018. The Company has agreements with certain remaining employees that provide for severance payments to the employee in the event the employee is terminated without cause or an employee terminates his employment for “good reason.” The maximum aggregate exposure under employment and severance agreements for remaining employees was approximately $5.4 million at September 30, 2018. In addition, in April 2018, the Board of Directors (the “Board”) of the Company adopted a long-term incentive plan, the Safeguard Scientifics Transaction Bonus Plan, (the “LTIP”). The purpose of the LTIP is to promote the interests of the Company and its shareholders by providing an additional incentive to employees to maximize the value of the Company in connection with the execution of the business strategy that the Company adopted and announced in January 2018. Under the LTIP, participants may receive awards in connection with sales of the Company’s partner company assets (“Sale Transaction(s)”). At the Board’s sole discretion following a sale of partner company assets, the Company may, but has no obligation to, provide a bonus pool under the LTIP based on a range of transaction consideration and subject to a minimum amount of transaction consideration. All current officers and employees of the Company are eligible to participate in the LTIP. The Board, in its sole discretion, will determine the participants to whom awards are granted under the LTIP, and the amounts of the awards relating to the bonus pool, if any. The Board has no obligation to grant any awards under the LTIP, even if transaction consideration exceeds the established minimum amount under the plan. There are no amounts payable under the LTIP as of September 30, 2018. In June 2011, the Company's former partner company, Advanced BioHealing, Inc. (“ABH”) was acquired by Shire plc (“Shire”). Prior to the expiration of the escrow period in March 2012, Shire filed a claim against all amounts held in escrow related to the sale based principally upon a United States Department of Justice (“DOJ”) false claims act investigation relating to ABH (the “Investigation”). In connection with the Investigation, in July 2015 the Company received a Civil Investigation Demand-Documentary Material (“CID”) from the DOJ regarding ABH and Safeguard’s relationship with ABH. Pursuant to the CID, the Company provided the requested materials and information. To the Company’s knowledge, the CID was related to multiple qui tam (“whistleblower”) actions, one of which was filed in 2014 by an ex-employee of ABH that named the Company and one of the Company’s employees along with other entities and individuals as defendants. At this time, the DOJ has declined to pursue the qui tam action as it relates to the Company and such Company employee. In addition, in connection with the above matters, the Company and other former equity holders in ABH entered into a settlement and release with Shire, which resulted in the release to Shire of all amounts held in escrow related to the sale of ABH.

Equity	9 Months Ended
Equity	Sep. 30, 2018
Equity [Abstract]
Equity	Equity In July 2015, the Company's Board of Directors authorized the Company, from time to time and depending on market conditions, to repurchase up to $25.0 million of the Company's outstanding common stock. During 2016, the Company repurchased 0.4 million shares at an aggregate cost of $5.4 million with $14.6 million remaining for repurchase under the existing authorization. Under the Amended Credit Facility, we are restricted from repurchasing shares of our outstanding common stock and/or issuing dividends until such time as the Amended Credit Facility is repaid in full. In February 2018, the Company's Board of Directors adopted a tax benefits preservation plan (the "Plan") designed to protect and preserve the Company's ability to utilize its net operating loss carryforwards ("NOLs"). The Company submitted the Plan for shareholder ratification at its 2018 Annual Meeting of Shareholders and the Plan was ratified by shareholders. The purpose of the Plan is to preserve the Company's ability to use its NOLs, which would be substantially limited if the Company experienced an "ownership change" as defined under Section 382 of the Internal Revenue Code. In general, an ownership change would be deemed to have occurred if the Company's shareholders who are treated as owning five percent or more of the outstanding shares of Safeguard for purposes of Section 382 ("five-percent shareholders") collectively increase their aggregate ownership in the Company's overall shares outstanding by more than 50 percentage points. Whether this change has occurred would be measured by comparing each five-percent shareholder's current ownership as of the measurement date to such shareholders' lowest ownership percentage during the three-year period preceding the measurement date. To protect the Company's NOLs from being limited or permanently lost under Section 382, the Plan is intended to deter any person or group from acquiring beneficial ownership of 4.99% or more of the Company's outstanding common stock without the approval of the Board, reducing the likelihood of an unintended ownership change. Under the Plan, the Company will issue one preferred stock purchase right (the "Rights") for each share of Safeguard's common stock held by shareholders of record on March 2, 2018. The issuance of the Rights will not be taxable to Safeguard or its shareholders and will not affect Safeguard's reported earnings per share. The Rights will trade with Safeguard's common shares and will expire no later than February 19, 2021. The Rights and the Plan may also expire on an earlier date upon the occurrence of other events, including a determination by the Company's Board that the Plan is no longer necessary or desirable for the preservation of the Company's tax attributes or that no tax attributes may be carried forward (with such expiration occurring as of the beginning of the applicable taxable year). There can be no assurance that the Plan will prevent the Company from experiencing an ownership change.

General General (Policies)	9 Months Ended
General General (Policies)	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Restricted Cash Equivalents	Restricted Cash Equivalents Restricted cash equivalents in prior periods represented cash required to be set aside by a contractual agreement with a bank as collateral for a letter of credit. During the first quarter of 2018, the restriction on the cash lapsed in connection with the termination of the related letter of credit.
Recent Accounting Pronouncements	Recently Adopted Accounting Pronouncements In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities. ASU 2016-01 requires that equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) are to be measured at fair value with changes in fair value recognized in net income. However, an entity may choose to measure equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Furthermore, equity investments without readily determinable fair values are to be assessed for impairment using a qualitative approach. The amendments in ASU 2016-01 should be applied by means of a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption, with other amendments related specifically to equity securities without readily determinable fair values applied prospectively. The Company adopted the amendments in ASU 2016-01 when they became effective on January 1, 2018. The adoption of this guidance did not have a material impact upon the Company's financial condition or results of operations. In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASU 2014-09"). ASU 2014-09 and related subsequent amendments outline a single comprehensive model to use to account for revenue arising from contracts with customers and supersede most current revenue recognition guidance. For public companies, the guidance is effective for annual periods beginning after December 15, 2017 and any interim periods that fall within that reporting period. For nonpublic companies, the guidance is effective for annual periods beginning after December 15, 2018 and interim periods within annual periods beginning after December 15, 2019 with early adoption permitted. As the new standard will supersede most existing revenue guidance, it could impact revenue and cost recognition for partner companies. Any change in revenue or cost recognition for partner companies could affect the Company's recognition of its share of the results of its equity method partner companies. On July 20, 2017, the SEC staff observer at the FASB’s Emerging Issues Task Force ("EITF") meeting announced that the SEC staff will not object if a private company equity method investee meeting the definition of a public business entity that otherwise would not meet the definition of a public business entity except for the inclusion of its financial statements or financial information in another entity’s filings with the SEC, uses private company adoption dates for the new revenue standard. As a result, the Company's private, calendar year partner companies will adopt the new revenue standard for the year ending December 31, 2019. The impact of adoption of the new revenue standard will be reflected in the Company’s financial results for the interim and annual reporting periods beginning in 2020 on a one quarter-lag basis. Recently Issued Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02, Leases. The guidance in ASU 2016-02 requires that a lessee recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. As with previous guidance, there continues to be a differentiation between finance leases and operating leases, however this distinction now primarily relates to differences in the manner of expense recognition over time and in the classification of lease payments in the statement of cash flows. Lease assets and liabilities arising from both finance and operating leases will be recognized in the statement of financial position. The transitional guidance for adopting the requirements of ASU 2016-02 calls for a modified retrospective approach that includes a number of optional practical expedients that entities may elect to apply. The guidance in ASU 2016-02 will become effective for the Company on January 1, 2019. The Company anticipates making the accounting policy election not to recognize lease assets and lease liabilities for leases with a term of 12 months or less. As of September 30, 2018, the Company's only material long-term lease was for its corporate headquarters in Radnor, PA under a lease expiring in 2026. The Company also has immaterial office equipment leases expiring at various dates through 2020. The Company is currently evaluating the impact that the adoption of ASU 2016-02 will have on its consolidated financial statements.

General General (Tables)

9 Months Ended

Sep. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Cash and Cash Equivalents

The following table provides a reconciliation of cash, cash equivalents and restricted cash equivalents reported within the Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows:



	September 30, 2018		December 31, 2017
	(Unaudited - In thousands)
Cash and cash equivalents	$	44,522	$	20,751
Long-term restricted cash equivalents	—		6,336
Total cash, cash equivalents and restricted cash equivalents	$	44,522	$	27,087

Ownership Interests in and Advances to Partner Companies and Funds (Tables)

9 Months Ended

Sep. 30, 2018

Investments in and Advances to Affiliates, Schedule of Investments [Abstract]

Ownership Interests in and Advances to Partner Companies and Private Equity Funds

The following summarizes the carrying value of the Company’s ownership interests in and advances to partner companies.



	September 30, 2018		December 31, 2017
	(Unaudited - In thousands)
Equity Method Companies:
Partner companies	$	71,248	$	107,646
Private equity funds	440		443
	71,688		108,089
Other Companies:
Partner companies and other holdings	15,260		2,762
Private equity funds	1,311		1,334
	16,571		4,096
Advances to partner companies	15,443		22,506
	$	103,702	$	134,691

The Company’s active partner companies were as follows as of September 30, 2018:



Partner Company	Safeguard Primary Ownership as of September 30, 2018	Accounting Method
Aktana, Inc.	20.1%	Equity
Brickwork	20.3%	Equity
CloudMine, Inc.	47.3%	Equity
Clutch Holdings, Inc.	41.2%	Equity
Flashtalking ¹	10.3%	Other
Hoopla Software, Inc.	25.5%	Equity
InfoBionic, Inc.	25.4%	Equity
Lumesis, Inc.	43.8%	Equity
MediaMath, Inc.²	13.3%	Other
meQuilibrium	33.1%	Equity
Moxe Health Corporation	32.4%	Equity
NovaSom, Inc.	31.7%	Equity
Prognos (fka Medivo, Inc.)	28.7%	Equity
Propeller Health, Inc.	19.6%	Equity
QuanticMind, Inc.	24.7%	Equity
Sonobi, Inc.	21.6%	Equity
Syapse, Inc.	20.0%	Equity
T-REX Group, Inc.	21.1%	Equity
Transactis, Inc.	23.7%	Equity
Trice Medical, Inc.	23.4%	Equity
WebLinc, Inc.	37.9%	Equity
Zipnosis, Inc.	34.7%	Equity

¹Spongecell, Inc. merged into Flashtalking in January 2018.

²The Company sold 39.1% of its ownership interest in MediaMath, Inc. back to the company for $45.0 million of proceeds in July 2018.

Equity Method Investment Partner Company Results Of Operation



	Three months ended September 30,						Nine months ended September 30,
	2018			2017			2018			2017
	(Unaudited - In thousands)
Results of Operations:
Revenue	$	40,070		$	91,137		$	234,049		$	275,154
Gross profit	$	21,822		$	60,836		$	153,387		$	180,158
Net loss	$	(34,885	)	$	(52,648	)	$	(120,971	)	$	(148,439	)

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Carrying Value and Fair Value of Certain Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table provides the carrying value and fair value of certain financial assets and liabilities of the Company measured at fair value on a recurring basis as of September 30, 2018 and December 31, 2017:



	Carrying Value		Fair Value Measurement at September 30, 2018
	Carrying Value		Level 1		Level 2		Level 3
	(Unaudited - In thousands)
Cash and cash equivalents	$	44,522	$	44,522	$	—	$	—
Trading securities	1,307		1,307		—		—
Marketable securities—held-to-maturity:
Certificates of deposit	249		—		249		—
Government agency bond	$	8,471	$	8,471	$	—	$	—
U.S. Treasury Bills	$	16,394	$	16,394	$	—	$	—
Total marketable securities	$	25,114	$	24,865	$	249	$	—

Credit facility repayment feature liability	$	5,622	$	—	$	—	$	5,622



	Carrying Value		Fair Value Measurement at December 31, 2017
	Carrying Value		Level 1		Level 2		Level 3
	(Unaudited - In thousands)
Cash and cash equivalents	$	20,751	$	20,751	$	—	$	—
Long-term restricted cash equivalents	6,336		6,336		—		—
Trading securities	3,761		3,761		—		—
Marketable securities—held-to-maturity:
Certificates of deposit	$	4,452	$	4,452	$	—	$	—

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation Expense

Stock-based compensation expense was recognized in the Consolidated Statements of Operations as follows:



	Three months ended September 30,				Nine months ended September 30,
	2018		2017		2018		2017
	(Unaudited - In thousands)
General and administrative expense	$	243	$	560	$	853	$	806
	$	243	$	560	$	853	$	806

Net Income (Loss) Per Share (Tables)

9 Months Ended

Sep. 30, 2018

Earnings Per Share [Abstract]

Calculations of Net Loss Per Share

The calculations of net income (loss) per share were as follows:



	Three months ended September 30,					Nine months ended September 30,
	2018		2017			2018		2017
	(Unaudited - In thousands, except per share data)
Basic:
Net income (loss)	$	32,060	$	(18,650	)	$	994	$	(69,844	)
Weighted average common shares outstanding	20,561		20,455			20,535		20,416
Net income (loss) per share	$	1.56	$	(0.91	)	$	0.05	$	(3.42	)

Diluted:
Net income (loss) for dilutive share computation	$	32,060	$	(18,650	)	$	994	$	(69,844	)

Number of shares used in basic per share computation	20,561		20,455			20,535		20,416
Unvested restricted stock and DSU's	—		—			—		—
Employee stock options	—		—			—		—
Weighted average common shares outstanding	20,561		20,455			20,535		20,416

Net income (loss) for dilutive share computation	$	1.56	$	(0.91	)	$	0.05	$	(3.42	)

Segment Reporting (Tables)

9 Months Ended

Sep. 30, 2018

Segment Reporting [Abstract]

Active Partner Companies by Segment

The following summarizes the carrying value of the Company’s ownership interests in and advances to partner companies.



	September 30, 2018		December 31, 2017
	(Unaudited - In thousands)
Equity Method Companies:
Partner companies	$	71,248	$	107,646
Private equity funds	440		443
	71,688		108,089
Other Companies:
Partner companies and other holdings	15,260		2,762
Private equity funds	1,311		1,334
	16,571		4,096
Advances to partner companies	15,443		22,506
	$	103,702	$	134,691

The Company’s active partner companies were as follows as of September 30, 2018:



Partner Company	Safeguard Primary Ownership as of September 30, 2018	Accounting Method
Aktana, Inc.	20.1%	Equity
Brickwork	20.3%	Equity
CloudMine, Inc.	47.3%	Equity
Clutch Holdings, Inc.	41.2%	Equity
Flashtalking ¹	10.3%	Other
Hoopla Software, Inc.	25.5%	Equity
InfoBionic, Inc.	25.4%	Equity
Lumesis, Inc.	43.8%	Equity
MediaMath, Inc.²	13.3%	Other
meQuilibrium	33.1%	Equity
Moxe Health Corporation	32.4%	Equity
NovaSom, Inc.	31.7%	Equity
Prognos (fka Medivo, Inc.)	28.7%	Equity
Propeller Health, Inc.	19.6%	Equity
QuanticMind, Inc.	24.7%	Equity
Sonobi, Inc.	21.6%	Equity
Syapse, Inc.	20.0%	Equity
T-REX Group, Inc.	21.1%	Equity
Transactis, Inc.	23.7%	Equity
Trice Medical, Inc.	23.4%	Equity
WebLinc, Inc.	37.9%	Equity
Zipnosis, Inc.	34.7%	Equity

¹Spongecell, Inc. merged into Flashtalking in January 2018.

²The Company sold 39.1% of its ownership interest in MediaMath, Inc. back to the company for $45.0 million of proceeds in July 2018.

General General (Details) - USD ($)		1 Months Ended			3 Months Ended	9 Months Ended		12 Months Ended
General General (Details) - USD ($)	May 15, 2018	Jul. 26, 2018	May 31, 2018	May 31, 2017	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Apr. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Cash and cash equivalents					$ 44,522,000	$ 44,522,000				$ 20,751,000
Marketable securities					25,100,000	25,100,000
Cash, cash equivalents, and marketable securities					69,600,000	69,600,000
Proceeds from sale of equity method investments		$ 55,000,000
Severance costs					1,000,000	3,800,000
Cash and cash equivalents					44,522,000	44,522,000				20,751,000
Long-term restricted cash equivalents					0	0				6,336,000
Total cash, cash equivalents and restricted cash equivalents					44,522,000	44,522,000	$ 40,653,000			$ 27,087,000	$ 28,394,000
Proceeds from credit facility						35,000,000	$ 50,000,000
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Liquidity threshold				$ 20,000,000
Minimum aggregate appraised value plus liquidity threshold				350,000,000
Scenario, Forecast
Debt Instrument [Line Items]
Severance costs								$ 4,000,000
Scenario, Forecast \| Minimum
Debt Instrument [Line Items]
Projected annual cost savings								8,000,000
Scenario, Forecast \| Maximum
Debt Instrument [Line Items]
Projected annual cost savings								$ 9,000,000
MediaMath, Inc.
Debt Instrument [Line Items]
Percent of ownership sold		39.13%
Proceeds from sale of equity method investments		$ 45,000,000
Percent of ownership sold, repurchase option within 180 days		10.87%
Repurchase option within 180 days		$ 12,500,000
AdvantEdge Healthcare Solutions, Inc.
Debt Instrument [Line Items]
Proceeds from sale of equity method investments		10,000,000
Additional amount receivable after certain valuation thresholds		$ 6,300,000
Amended Credit Facility
Debt Instrument [Line Items]
Current borrowing capacity					15,000,000	15,000,000
Maximum borrowing capacity			$ 100,000,000.0
Cash and cash equivalent threshold			50,000,000		50,000,000	50,000,000
Long-term line of credit outstanding					$ 85,000,000	$ 85,000,000
Liquidity threshold			20,000,000
Minimum aggregate appraised value plus liquidity threshold			350,000,000
Deployment threshold			40,000,000.0
Expense threshold			11,500,000.0
Amended Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			15,000,000.0
Amended Credit Facility \| Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity			85,000,000.0
Long-term line of credit outstanding			35,000,000						$ 50,000,000
Proceeds from credit facility			$ 32,700,000
Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				75,000,000.0
Long-term line of credit outstanding				50,000,000
Proceeds from credit facility				$ 44,300,000
2018 Debentures
Debt Instrument [Line Items]
Repayments of debt	$ 41,000,000

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Ownership Interests in and Advances to Partner Companies and Funds - Carrying Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Investments In And Advances To Affiliates [Line Items]
Equity method investments	$ 71,688	$ 108,089
Cost method investments	16,571	4,096
Advances to partner companies	15,443	22,506
Investments in and advance to affiliates, subsidiaries, associates, and joint ventures	103,702	134,691
Partner companies
Investments In And Advances To Affiliates [Line Items]
Equity method investments	71,248	107,646
Cost method investments	15,260	2,762
Private equity funds
Investments In And Advances To Affiliates [Line Items]
Equity method investments	440	443
Cost method investments	$ 1,311	$ 1,334

Ownership Interests in and Advances to Partner Companies and Funds - Narrative (Detail) - USD ($)	1 Months Ended						3 Months Ended		9 Months Ended
	Jul. 26, 2018	May 31, 2018	Feb. 28, 2018	Jan. 31, 2018	Aug. 31, 2017	Mar. 31, 2017	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Dec. 31, 2017	Mar. 03, 2017
Investment [Line Items]
Equity method investments							$ 71,688,000		$ 71,688,000			$ 108,089,000
Proceeds from sale of equity method investments	$ 55,000,000
Proceeds from sale of business									69,912,000	$ 16,604,000
Beyond.com, Inc
Investment [Line Items]
Repayments of debt			$ 10,500,000
CloudMine
Investment [Line Items]
Other than temporary impairment							4,800,000		4,800,000
Equity method investments											$ 10,500,000
Cask Data
Investment [Line Items]
Equity method investments								$ 13,300,000
Proceeds from sale of equity method investments		$ 11,500,000
Realized gain (loss) on disposal							4,200,000		4,200,000
Amount in holdbacks and escrows		$ 2,400,000
MediaMath, Inc.
Investment [Line Items]
Percent of ownership sold	39.13%
Proceeds from sale of equity method investments	$ 45,000,000
Percent of ownership sold, repurchase option within 180 days	10.87%
Repurchase option within 180 days	$ 12,500,000
Realized gain (loss) on disposal									45,000,000
AdvantEdge Healthcare Solutions, Inc.
Investment [Line Items]
Proceeds from sale of equity method investments	10,000,000
Realized gain (loss) on disposal							5,500,000		5,500,000
Additional amount receivable after certain valuation thresholds	$ 6,300,000
Apprenda
Investment [Line Items]
Other than temporary impairment									6,600,000
Equity method investments							$ 0		0
Beyond.com, Inc
Investment [Line Items]
Consideration received per transaction						$ 26,000,000
Proceeds from sale of business			$ 10,500,000			$ 15,500,000
Term of note receivable (in years)						3 years
Amount of consideration received						$ 10,500,000
Interest rate on note receivable													9.50%
Loans receivable, net						$ 10,500,000						0
Gain on sale of business									9,500,000
Flashtalking
Investment [Line Items]
Noncontrolling interest, ownership percentage by noncontrolling owners				10.00%
Cost method investments, original cost				$ 11,200,000
Cost-method investments, realized gain (loss)									3,900,000
Invitae Corporation
Investment [Line Items]
Trading securities sold			414,237				78,103
Proceeds from sale of trading securities held-for-investment			$ 2,600,000					$ 2,600,000
Number of shares received (in shares)					414,237
Number of shares received, amount held in escrow (in shares)					124,092
Trading securities, realized gain (loss)							$ (1,100,000)		(1,100,000)
Trading securities, equity							1,300,000		1,300,000			$ 3,800,000
Unrealized holding gain (loss)							$ 200,000		(1,000,000)
Aventura
Investment [Line Items]
Proceeds from sale of equity method investments				$ 600,000
Realized gain (loss) on disposal									$ 600,000

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Ownership Interests in and Advances to Partner Companies and Funds - Schedule of Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Investments in and Advances to Affiliates [Abstract]
Revenue	$ 40,070	$ 91,137	$ 234,049	$ 275,154
Gross profit	21,822	60,836	153,387	180,158
Net loss	$ (34,885)	$ (52,648)	$ (120,971)	$ (148,439)

Acquisitions of Ownership Interests in Partner Companies and Funds (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments				$ 3,250	$ 11,851
Equity method investments	$ 71,688			71,688		$ 108,089
InfoBionic
Schedule of Equity Method Investments [Line Items]
Equity method investments	21,300			21,300
Convertible bridge loan	700	$ 800	$ 800
meQuilibrium
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	1,000
Equity method investments	10,500			10,500
Moxe Health
Schedule of Equity Method Investments [Line Items]
Equity method investments	4,500			4,500
Convertible bridge loan	1,000
Zipnosis
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	1,500
Equity method investments	7,000			7,000
CloudMine
Schedule of Equity Method Investments [Line Items]
Equity method investments		10,500
Convertible bridge loan	400	500
Aktana, Inc.
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	500
Equity method investments	9,700			9,700
QuanticMind, Inc.
Schedule of Equity Method Investments [Line Items]
Equity method investments	11,500			11,500
Convertible bridge loan	1,400
Sonobi
Schedule of Equity Method Investments [Line Items]
Equity method investments	10,900			$ 10,900
Convertible bridge loan	$ 500	1,500	200
WebLinc
Schedule of Equity Method Investments [Line Items]
Equity method investments			14,500
Convertible bridge loan		200	500
Propeller
Schedule of Equity Method Investments [Line Items]
Equity method investments			14,000
Convertible bridge loan		300
Cask Data
Schedule of Equity Method Investments [Line Items]
Equity method investments			13,300
Convertible bridge loan		200	300
Novasom, Inc.
Schedule of Equity Method Investments [Line Items]
Equity method investments			25,400
Convertible bridge loan		$ 800	1,300
Spongecell
Schedule of Equity Method Investments [Line Items]
Equity method investments						18,600
Convertible bridge loan			500
BrickWork
Schedule of Equity Method Investments [Line Items]
Equity method investments						$ 4,200
Convertible bridge loan			$ 400

Fair Value Measurements - Carrying Value and Fair Value of Certain Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term restricted cash equivalents	$ 0	$ 6,336
Trading securities	1,307	3,761
Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	44,522	20,751
Long-term restricted cash equivalents		6,336
Trading securities	1,307	3,761
Marketable securities—held-to-maturity:	25,114
Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	249	4,452
Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Government agency bond
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	8,471
Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring \| U.S. Treasury Bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	16,394
Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Credit facility repayment feature liability	5,622
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	44,522	20,751
Long-term restricted cash equivalents		6,336
Trading securities	1,307	3,761
Marketable securities—held-to-maturity:	24,865
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Long-term restricted cash equivalents		0
Trading securities	0	0
Marketable securities—held-to-maturity:	249
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Long-term restricted cash equivalents		0
Trading securities	0	0
Marketable securities—held-to-maturity:	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Certificates of deposit \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	0	4,452
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Certificates of deposit \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	249	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Certificates of deposit \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	0	$ 0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Government agency bond \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	8,471
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Government agency bond \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Government agency bond \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| U.S. Treasury Bills \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	16,394
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| U.S. Treasury Bills \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| U.S. Treasury Bills \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities—held-to-maturity:	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Debt \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Credit facility repayment feature liability	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Debt \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Credit facility repayment feature liability	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring \| Debt \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Credit facility repayment feature liability	$ 5,622

Fair Value Measurements - Narrative (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Feb. 28, 2018	Aug. 31, 2017	Sep. 30, 2018	Mar. 31, 2018	Jun. 30, 2018	May 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities, current			$ 25,114				$ 4,452
Amended Credit Facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Credit facility repayment feature			5,600		$ 2,600	$ 500
Cash and cash equivalent threshold			$ 50,000			$ 50,000
Good Start Genetics, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of shares received (in shares)		414,237	78,103
Invitae Corporation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of shares received (in shares)		414,237
Proceeds from sale of trading securities held-for-investment	$ 2,600			$ 2,600

Credit Facility and Convertible Debentures - Credit Arrangements Narrative (Detail) - USD ($)			1 Months Ended			3 Months Ended		9 Months Ended
	Oct. 15, 2018	May 15, 2018	Jul. 26, 2018	May 31, 2018	May 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Apr. 30, 2018
Debt Instrument [Line Items]
Proceeds from credit facility								$ 35,000,000	$ 50,000,000
Gain (loss) from covenant liability						$ (2,600,000)		(5,100,000)
Proceeds from sale of equity method investments			$ 55,000,000
Interest expense						3,310,000	$ 2,643,000	9,422,000	5,953,000
Convertible Debt
Debt Instrument [Line Items]
Interest expense						0	900,000	1,300,000	3,200,000
Debt instrument, interest rate, effective percentage										8.70%
Interest paid						0	0	1,100,000	1,500,000
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Liquidity threshold					$ 20,000,000
Minimum aggregate appraised value plus liquidity threshold					350,000,000
Interest expense						3,300,000	1,700,000	8,000,000	2,600,000
Debt instrument, interest rate, effective percentage										14.90%
Interest paid						2,400,000	$ 1,200,000	4,900,000	$ 1,200,000
Credit Facility
Debt Instrument [Line Items]
Interest and prepayment fee percent				100.00%
Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity					75,000,000.0
Long-term line of credit outstanding					50,000,000
Proceeds from credit facility					$ 44,300,000
Debt instrument, term (in years)					3 years
Interest payable amount outstanding threshold					$ 50,000,000
Commitment fee percentage					0.75%
Credit Facility \| Revolving Credit Facility \| Interest Rate Application A \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate					8.50%
Credit Facility \| Revolving Credit Facility \| Interest Rate Application A \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate					1.00%
Credit Facility \| Revolving Credit Facility \| Interest Rate Application B
Debt Instrument [Line Items]
Basis spread on variable rate					2.00%
Credit Facility \| Revolving Credit Facility \| Interest Rate Application B \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate					7.50%
Credit Facility \| Revolving Credit Facility \| Interest Rate Application B \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate					1.00%
Credit Facility \| Revolving Credit Facility \| Interest Rate Application B \| Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Basis spread on variable rate					0.50%
Amended Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 100,000,000.0
Long-term line of credit outstanding						85,000,000		85,000,000
Cash and cash equivalent threshold				50,000,000		50,000,000		50,000,000
Liquidity threshold				20,000,000
Minimum aggregate appraised value plus liquidity threshold				350,000,000
Deployment threshold				40,000,000.0
Expense threshold				11,500,000.0
Unamortized discount and debt issuance costs						5,200,000		5,200,000
Long-term debt						79,800,000		79,800,000
Credit facility repayment feature				500,000		$ 5,600,000		$ 5,600,000		$ 2,600,000
Amended Credit Facility \| Subsequent Event
Debt Instrument [Line Items]
Repayments of lines of credit	$ 16,400,000
Periodic payment, interest	$ 2,800,000
Amended Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				15,000,000.0
Amended Credit Facility \| Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity				85,000,000.0
Long-term line of credit outstanding				35,000,000							$ 50,000,000
Proceeds from credit facility				$ 32,700,000
2018 Debentures
Debt Instrument [Line Items]
Repayments of debt		$ 41,000,000

Credit Facility and Convertible Debentures - Convertible Senior Debentures Narrative (Detail) - USD ($)		2 Months Ended	3 Months Ended		9 Months Ended
	May 15, 2018	Jul. 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Nov. 30, 2012
Debt Instrument [Line Items]
Interest expense			$ 3,310,000	$ 2,643,000	$ 9,422,000	$ 5,953,000
2018 Debentures
Debt Instrument [Line Items]
Repayments of debt	$ 41,000,000
Convertible Debt
Debt Instrument [Line Items]
Aggregate face value of convertible senior debentures								$ 55,000,000.0
Interest rate on debentures								5.25%
Repurchased face amount		$ 14,000,000
Repayments of long-term debt		$ 14,500,000
Interest expense			0	900,000	1,300,000	3,200,000
Debt instrument, interest rate, effective percentage							8.70%
Interest paid			$ 0	$ 0	$ 1,100,000	$ 1,500,000

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 243	$ 560	$ 853	$ 806
General And Administrative Expenses
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 243	$ 560	$ 853	$ 806

Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
Income Taxes (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax benefit (expense)	$ 0	$ 0	$ 0	$ 0
Provisional income tax expense (benefit)					$ 82,500

Net Income (Loss) Per Share - Calculations of Net Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic:
Net income (loss)	$ 32,060	$ (18,650)	$ 994	$ (69,844)
Weighted average common shares outstanding (in shares)	20,561	20,455	20,535	20,416
Net income (loss) per share (in dollars per share)	$ 1.56	$ (0.91)	$ 0.05	$ (3.42)
Diluted:
Unvested restricted stock and DSU's	0	0	0	0
Employee stock options	0	0	0	0
Weighted average common shares outstanding	$ 20,561	$ 20,455	$ 20,535	$ 20,416
Net income (loss) for dilutive share computation	$ 0	$ 0	$ 0	$ 0

Net Income (Loss) Per Share - Narrative (Detail) - $ / shares shares in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share of common stock excluded from diluted net loss per share calculation (in shares)	0.4	0.6
Shares of common stock at prices ranging, lower limit (in dollars per share)	$ 9.83	$ 9.83
Shares of common stock at prices ranging, upper limit (in dollars per share)	$ 19.95	$ 19.95
Deferred stock units, performance-based stock units and restricted stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share of common stock excluded from diluted net loss per share calculation (in shares)	0.8	0.9
Convertible Senior Debentures due 2018
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share of common stock excluded from diluted net loss per share calculation (in shares)	1.1	2.3

Segment Reporting - Narrative (Detail)	9 Months Ended
Segment Reporting - Narrative (Detail)	Sep. 30, 2018 segment nonconsolidated_partner_company
Segment Reporting [Abstract]
Number of operating segments \| segment	1
Non-consolidated partner companies \| nonconsolidated_partner_company	22

Segment Reporting - Active Partner Companies by Segment (Detail) - USD ($) $ in Millions	1 Months Ended
	Jul. 26, 2018	Sep. 30, 2018
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of equity method investments	$ 55.0
BrickWork
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		20.30%
CloudMine
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		47.30%
Clutch Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		41.20%
Flashtalking
Schedule of Equity Method Investments [Line Items]
Ownership interest under cost method, percentage		10.30%
Hoopla Software, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		25.50%
Lumesis, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		43.80%
MediaMath, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		13.30%
Percent of ownership sold	39.13%
Proceeds from sale of equity method investments	$ 45.0
Moxe Health
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		32.40%
Prognos
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		28.70%
QuanticMind, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		24.70%
Sonobi
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		21.60%
T-REX Group, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		21.10%
Transactis
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		23.70%
WebLinc
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		37.90%
Healthcare \| Aktana, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		20.10%
Healthcare \| InfoBionic
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		25.40%
Healthcare \| meQuilibrium
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		33.10%
Healthcare \| Novasom, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		31.70%
Healthcare \| Propeller
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		19.60%
Healthcare \| Syapse, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		20.00%
Healthcare \| Trice
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		23.40%
Healthcare \| Zipnosis
Schedule of Equity Method Investments [Line Items]
Ownership interest under equity method, percentage		34.70%

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Commitments and Contingencies (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Oct. 31, 2001	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017
Commitment Contingencies And Guarantees [Line Items]
Other long-term liabilities		$ 3,106	$ 3,106			$ 3,535
Annual payments	$ 650
Severance costs		1,000	3,800
Payments for restructuring		1,000	1,500
Employee Severance
Commitment Contingencies And Guarantees [Line Items]
Maximum severance payments		5,400	5,400
Scenario, Forecast
Commitment Contingencies And Guarantees [Line Items]
Severance costs				$ 4,000
Letter of credit
Commitment Contingencies And Guarantees [Line Items]
Letter of credit under the credit facility					$ 6,300
Accrued expenses and other current liabilities
Commitment Contingencies And Guarantees [Line Items]
Liability to former chairman and chief executive officer, current		800	800
Other long-term liabilities
Commitment Contingencies And Guarantees [Line Items]
Liability to former chairman and chief executive officer, non-current		1,400	1,400
Accrued Compensation and Benefits
Commitment Contingencies And Guarantees [Line Items]
Severance costs			2,300
Clawback Liability
Commitment Contingencies And Guarantees [Line Items]
Other long-term liabilities		$ 300	$ 300
Company's ownership in the funds		19.00%	19.00%
Clawback liability paid							$ 1,000
Private equity funds
Commitment Contingencies And Guarantees [Line Items]
Company outstanding guarantees		$ 3,800	$ 3,800

Equity (Details) - USD ($) shares in Millions	1 Months Ended	12 Months Ended
Equity (Details) - USD ($) shares in Millions	Feb. 28, 2018	Dec. 31, 2016	Jul. 31, 2015
Equity, Class of Treasury Stock [Line Items]
Individual ownership percent maximum	4.99%
Common Stock
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount			$ 25,000,000.0
Repurchase of common stock (in shares)		0.4
Stock repurchased during period, value		$ 5,400,000
Remaining authorized repurchase amount		$ 14,600,000

Subsequent Events (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Subsequent Events (Details) - USD ($) $ in Millions	Jul. 26, 2018	Sep. 30, 2018	Sep. 30, 2018
Subsequent Event [Line Items]
Proceeds from sale of equity method investments	$ 55.0
MediaMath, Inc.
Subsequent Event [Line Items]
Percent of ownership sold	39.13%
Proceeds from sale of equity method investments	$ 45.0
Percent of ownership sold, repurchase option within 180 days	10.87%
Repurchase option within 180 days	$ 12.5
Realized gain (loss) on disposal			$ 45.0
AdvantEdge Healthcare Solutions, Inc.
Subsequent Event [Line Items]
Proceeds from sale of equity method investments	10.0
Realized gain (loss) on disposal		$ 5.5	$ 5.5
Additional amount receivable after certain valuation thresholds	$ 6.3

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