Intangible Assets (Summary of Amortizing and Indefinite-Lived Intangibles) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Intangible Assets [Line Items]
Intangible assets, gross	$ 1,686,875	$ 1,705,575
Intangible assets, cumulative amortization	(61,602)	(54,631)
Intangible assets, cumulative impairment	(184,274)	(184,274)
Intangible assets, net	1,440,999	1,466,670
Amortizing intangibles:
Gross carrying value	157,803	156,503
Cumulative amortization	(27,642)	(20,671)
Cumulative impairment losses	0	0
Intangible assets, net	130,161	135,832
Indefinite lived intangible assets:
Gross carrying value	1,529,072	1,549,072
Cumulative amortization	(33,960)	(33,960)
Cumulative impairment losses	(184,274)	(184,274)
Intangible assets, net	$ 1,310,838	$ 1,330,838
Customer Relationships [Member]
Amortizing intangibles:
Weighted average life	4 years	7 years 3 months 24 days
Gross carrying value	$ 66,700	$ 65,400
Cumulative amortization	(21,062)	(15,113)
Cumulative impairment losses	0	0
Intangible assets, net	$ 45,638	$ 50,287
Off-Market Favorable Lease [Member]
Amortizing intangibles:
Weighted average life	36 years 9 months	37 years
Gross carrying value	$ 11,730	$ 11,730
Cumulative amortization	(3,358)	(3,302)
Cumulative impairment losses	0	0
Intangible assets, net	8,372	8,428
Development Agreement
Amortizing intangibles:
Gross carrying value	21,373	21,373
Cumulative amortization	0	0
Cumulative impairment losses	0	0
Intangible assets, net	$ 21,373	$ 21,373
Other Intangible Assets [Member]
Amortizing intangibles:
Weighted average life	14 years 2 months 24 days	14 years 4 months 24 days
Gross carrying value	$ 58,000	$ 58,000
Cumulative amortization	(3,222)	(2,256)
Cumulative impairment losses	0	0
Intangible assets, net	54,778	55,744
Trademarks
Indefinite lived intangible assets:
Gross carrying value	207,387	207,387
Cumulative amortization	0	0
Cumulative impairment losses	(4,300)	(4,300)
Intangible assets, net	203,087	203,087
Gaming License Rights
Indefinite lived intangible assets:
Gross carrying value	1,321,685	1,341,685
Cumulative amortization	(33,960)	(33,960)
Cumulative impairment losses	(179,974)	(179,974)
Intangible assets, net	$ 1,107,751	$ 1,127,751

Cumulative Impairment of Intangible Assets (Excluding Goodwill)

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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