| **Cover**                                   | Oct. 30, 2019                            |
|---------------------------------------------|------------------------------------------|
| **Cover page.**                             |                                     |
| Document Type                               | 8-K                                      |
| Document Period End Date                    | Oct. 30,  2019                           |
| Entity Registrant Name                      | Churchill Downs Incorporated             |
| Entity Incorporation, State or Country Code | KY                                       |
| Entity File Number                          | 001-33998                                |
| Entity Tax Identification Number            | 61-0156015                               |
| Entity Address, Address Line One            | 600 North Hurstbourne Parkway, Suite 400 |
| Entity Address, City or Town                | Louisville                               |
| Entity Address, State or Province           | KY                                       |
| Entity Address, Postal Zip Code             | 40222                                    |
| City Area Code                              | 502                                      |
| Local Phone Number                          | 636-4400                                 |
| 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                              | CHDN                                     |
| Security Exchange Name                      | NASDAQ                                   |
| Entity Emerging Growth Company              | false                                    |
| Amendment Flag                              | false                                    |
| Entity Central Index Key                    | 0000020212                               |

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