The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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- Definition

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+ References

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- Definition

Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

+ References

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- Definition

Amount of fair value of reporting unit in excess of carrying amount.

+ References

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Asset Impairment (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Asset Impairment (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Indefinite-lived Intangible Assets [Line Items]
Impairment of intangible assets		$ 17.5	$ 0.0	$ 0.0
Presque Isle
Indefinite-lived Intangible Assets [Line Items]
Fair value	$ 62.6
Presque Isle \| Gaming
Indefinite-lived Intangible Assets [Line Items]
Impairment of intangible assets	12.5
Gaming rights \| Presque Isle
Indefinite-lived Intangible Assets [Line Items]
Carrying value	77.6
Impairment of intangible assets	15.0
Gaming rights \| Presque Isle \| Online Wagering
Indefinite-lived Intangible Assets [Line Items]
Impairment of intangible assets	2.5
Trademarks \| Presque Isle
Indefinite-lived Intangible Assets [Line Items]
Impairment of intangible assets	$ 2.5