Fair Value Measurements - Significant Unobservable Inputs For Level 3 Assets and Liabilities (Details) $ in Millions	Mar. 31, 2020 USD ($)
Gaming licenses
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, fair value	$ 568.0
Trademarks
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, fair value	216.5
Level 3 \| Gaming licenses
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, fair value	568.0
Level 3 \| Trademarks
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, fair value	$ 216.5
Level 3 \| Discounted cash flow \| Discount rate \| Gaming licenses \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.1325
Level 3 \| Discounted cash flow \| Discount rate \| Gaming licenses \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.140
Level 3 \| Discounted cash flow \| Discount rate \| Trademarks \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.1325
Level 3 \| Discounted cash flow \| Discount rate \| Trademarks \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.140
Level 3 \| Discounted cash flow \| Long-term revenue growth rate \| Gaming licenses
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.020
Level 3 \| Discounted cash flow \| Long-term revenue growth rate \| Trademarks
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.020
Level 3 \| Discounted cash flow \| Pre-tax royalty rate \| Trademarks \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.010
Level 3 \| Discounted cash flow \| Pre-tax royalty rate \| Trademarks \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Indefinite-lived intangible assets, measurement input	0.020
Plainridge Park Casino \| Level 3 \| Discounted cash flow \| Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration, measurement input	0.1145

Indefinite-Lived Intangible Asset, Measurement Input

No definition available.

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- Definition

Value of input used to measure contingent consideration liability from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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