Employee Stock Purchase Plan, Award Period

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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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- 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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-Publisher FASB
-Name Accounting Standards Codification
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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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Stock-Based Compensation Plans - Additional Information (Details) $ in Millions		1 Months Ended	12 Months Ended
	Feb. 24, 2016	Oct. 31, 2018	Dec. 31, 2019 USD ($) service_period	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 23.8	$ 21.1	$ 27.1
Income tax benefit related to stock-based employee compensation			2.1	2.7	5.5
Fair value of shares and units vested			$ 36.9	$ 32.4	$ 29.6
Award period			1 year
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			3 years
2018 RSU Awards \| Restricted Stock Units (RSU)
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		7 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”) \| Performance Share Units (PSU)
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%
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			$ 23.8	$ 17.7	$ 16.0
Minimum \| Executive Long-Term Incentive Compensation Plan (the “ELTI Plan”) \| 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)		0.00%
Maximum \| Executive Long-Term Incentive Compensation Plan (the “ELTI Plan”) \| 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%