Marketable Securities, Eldorado Resorts, Inc. - Fair Value to Amortized Cost Basis (Details) - Eldorado - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Schedule of Equity Method Investments [Line Items]
Net operating revenues	$ 183,540	$ 78,949	$ 533,624	$ 197,728
Operating income (loss)	24,092	2,778	59,235	11,105
Net income (loss)	$ 5,399	$ (4,064)	$ 4,030	$ (3,488)