Marketable Securities, Eldorado Resorts, Inc.- Fair Value to Amortized Cost Basis (Details) - Eldorado - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Schedule of Equity Method Investments [Line Items]
Net operating revenues	$ 182,633	$ 61,749	$ 350,084	$ 118,779
Operating income	23,059	6,775	35,143	8,327
Net income	$ 4,795	$ 2,909	$ (1,369)	$ 576