Goodwill and Other Intangible Assets - Goodwill (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Goodwill [Roll Forward]
Balances as of December 31, 2019	$ 367.1
Adjustments	(0.3)
Balances as of September 30, 2020	366.8
Churchill Downs
Goodwill [Roll Forward]
Balances as of December 31, 2019	49.7
Adjustments	0.0
Balances as of September 30, 2020	49.7
Online Wagering
Goodwill [Roll Forward]
Balances as of December 31, 2019	148.2
Adjustments	0.0
Balances as of September 30, 2020	148.2
Gaming
Goodwill [Roll Forward]
Balances as of December 31, 2019	165.2
Adjustments	0.0
Balances as of September 30, 2020	165.2
All Other
Goodwill [Roll Forward]
Balances as of December 31, 2019	4.0
Adjustments	(0.3)
Balances as of September 30, 2020	$ 3.7

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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