| **Segment Information - Summary of Capital Expenditures (Details) - USD ($) $ in Millions** | 6 Months Ended |
|---------------------------------------------------------------------------------------------|----------------|
||
| **Segment Reporting, Asset Reconciling Item [Line Items]**                                  |           |   |
| Capital expenditures                                                                        | $ 167.1        | $ 29.6 |
| Operating Segments                                                                          |           |   |
| **Segment Reporting, Asset Reconciling Item [Line Items]**                                  |           |   |
| Capital expenditures                                                                        | 166.2          | 28.2 |
| Operating Segments | Live and Historical Racing                                             |           |   |
| **Segment Reporting, Asset Reconciling Item [Line Items]**                                  |           |   |
| Capital expenditures                                                                        | 119.8          | 16.9 |
| Operating Segments | TwinSpires                                                             |           |   |
| **Segment Reporting, Asset Reconciling Item [Line Items]**                                  |           |   |
| Capital expenditures                                                                        | 6.0            | 4.8 |
| Operating Segments | Gaming                                                                 |           |   |
| **Segment Reporting, Asset Reconciling Item [Line Items]**                                  |           |   |
| Capital expenditures                                                                        | 40.4           | 6.5 |
| All Other                                                                                   |           |   |
| **Segment Reporting, Asset Reconciling Item [Line Items]**                                  |           |   |
| Capital expenditures                                                                        | $ 0.9          | $ 1.4 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
+ References
No definition available.
+ Details**Name:**us-gaap_PropertyPlantAndEquipmentAdditions**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
+ Details**Name:**us-gaap_SegmentReportingAssetReconcilingItemLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=chdn_LiveAndHistoricalRacingMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=chdn_TwinSpiresMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=chdn_GamingSegmentMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |