Employee Stock Purchase Plan, Award Period

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- Definition

Number Of Named Executive Officers

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number Of Performance Criteria

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Requisite Service Periods

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Percentage of Original Award

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Payout Curve, Maximum Percentage of Original Award

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Percentage Decrease If In Bottom Quartile

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Percentage Increase in Awards If In Top Quartile

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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-Name Accounting Standards Codification
-Topic 718
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- Definition

Amount of noncash expense for share-based payment arrangement.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- 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.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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Stock-Based Compensation Plans - Additional Information (Details) $ in Millions			1 Months Ended	12 Months Ended
	Oct. 31, 2018 performanceCondition executiveOfficer	Feb. 24, 2016	Oct. 31, 2018 performanceCondition executiveOfficer	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) service_period	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 23.7	$ 23.8	$ 21.1
Income tax benefit related to stock-based employee compensation				1.9	2.1	2.7
Fair value of shares and units vested				$ 36.9	$ 36.9	$ 32.4
Award period				1 year
Restricted Stock Units (RSU) \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)				3 years
Churchill Downs Incorporated 2016 Omnibus Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		1 year
Churchill Downs Incorporated 2007 Omnibus Stock Incentive Plan \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)				3 years
Executive Long-Term Incentive Compensation Plan (the “ELTI Plan”) \| February 23, 2016 \| Performance Share Units (PSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award payout curve percentage of original performance share units awarded (as a percent)				200.00%
Percentage increase in awards if in top quartile				25.00%
Percentage decrease if in bottom quartile				25.00%
Maximum number of performance share units as percentage of original award (as a percent)				250.00%
7-Year Grant Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	7 years		7 years
Performance and service period under adopted ELTI Plan			3 years
Number of named executives \| executiveOfficer	2		2
Number of performance criteria \| performanceCondition	2		2
7-Year Grant Plan \| Performance Share Units (PSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			4 years
Performance and service period under adopted ELTI Plan			3 years
Maximum award payout curve percentage of original performance share units awarded (as a percent)	200.00%		200.00%
Award vesting (as a percent)			25.00%
7-Year Grant Plan \| Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			4 years
Award vesting (as a percent)			25.00%
Performance-Based Awards \| Executive Long-Term Incentive Compensation Plan (the “ELTI Plan”) \| February 23, 2016 \| Performance Share Units (PSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance and service period under adopted ELTI Plan					3 years	3 years	3 years
Requisite service periods \| service_period						3
Continuing Operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 23.7	$ 23.8	$ 17.7