Segment Information - Net Revenue From External Customers and Intercompany Revenue From Each Operating Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Net revenue	$ 628.5	$ 572.5	$ 2,110.1	$ 1,900.5
External Customer
Segment Reporting Information [Line Items]
Net revenue	628.5	572.5	2,110.1	1,900.5
Operating Segments \| Live and Historical Racing
Segment Reporting Information [Line Items]
Net revenue	247.5	219.5	957.3	818.9
Operating Segments \| TwinSpires
Segment Reporting Information [Line Items]
Net revenue	111.3	108.5	369.6	340.7
Operating Segments \| Gaming
Segment Reporting Information [Line Items]
Net revenue	269.7	244.3	783.1	740.2
Operating Segments \| External Customer
Segment Reporting Information [Line Items]
Net revenue	628.5	572.3	2,110.0	1,899.8
Operating Segments \| External Customer \| Live and Historical Racing
Segment Reporting Information [Line Items]
Net revenue	247.5	219.5	957.3	818.9
Operating Segments \| External Customer \| TwinSpires
Segment Reporting Information [Line Items]
Net revenue	111.3	108.5	369.6	340.7
Operating Segments \| External Customer \| Gaming
Segment Reporting Information [Line Items]
Net revenue	269.7	244.3	783.1	740.2
All Other
Segment Reporting Information [Line Items]
Net revenue	0.0	0.2	0.1	0.7
All Other \| External Customer
Segment Reporting Information [Line Items]
Net revenue	$ 0.0	$ 0.2	$ 0.1	$ 0.7

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Churchill Downs Inc 10-Q