Cover |
Jul. 02, 2019 |
|---|---|
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | On July 3, 2019, Morningstar, Inc. ("Morningstar") filed a Current Report on Form 8-K (the "Original Form 8-K") to announce that it had completed the acquisition of Ratings Acquisition Corp, an exempted company incorporated under the Laws of the Cayman Islands ("DBRS") for a purchase price of US$669 million (subject to adjustment) pursuant to the terms of the Agreement and Plan of Merger, dated as of May 28, 2019, by and among DBRS, Alpine Merger Co., a wholly-owned subsidiary of Morningstar, and Shareholder Representative Services LLC, as representative of the shareholders of DBRS. Morningstar is filing this Form 8-K/A as an amendment to the Original Form 8-K to provide audited and unaudited financial statements of DBRS and pro forma financial information required by Items 9.01(a) and (b) of Form 8-K, respectively. |
| Document Period End Date | Jul. 02, 2019 |
| Entity File Number | 000-51280 |
| Entity Registrant Name | MORNINGSTAR, INC. |
| Entity Central Index Key | 0001289419 |
| Entity Tax Identification Number | 36-3297908 |
| Entity Incorporation, State or Country Code | IL |
| Entity Address, Address Line One | 22 West Washington Street |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60602 |
| City Area Code | 312 |
| Local Phone Number | 696-6000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, no par value |
| Trading Symbol | MORN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |