Investment in Eldorado Financial Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Schedule of Equity Method Investments [Line Items]
Operating income	$ 8,797	$ 7,214	$ 15,788	$ 13,813
Net income	4,845	3,320	7,898	5,849
Eldorado
Schedule of Equity Method Investments [Line Items]
Net operating revenues	$ 65,828	$ 65,129	$ 128,007	$ 128,864