Summary of Significant Accounting Policies (Details 6)	12 Months Ended
	Dec. 31, 2012 item segment	Dec. 31, 2011	Dec. 31, 2010
Stock-Based Compensation
Time period of historical volatility of stock used to estimate expected volatility	6 years 7 months 20 days
Weighted-average assumptions used in the Black-Scholes option-pricing model
Risk-free interest rate (as a percent)	0.84%	1.04%	2.27%
Expected volatility (as a percent)	45.78%	47.60%	48.02%
Weighted-average expected life	6 years 7 months 20 days	5 years 9 months 25 days	5 years 8 months 23 days
Forfeiture rate (as a percent)	5.00%	5.00%	5.00%
Certain Risks and Uncertainties
Number of large properties in terms of net revenues that will face new significant competition in the near term	2
Segment Information
Number of senior vice presidents of regional operations	3
Number of reportable segments	3
Ownership interest in joint venture (as a percent)	50.00%
Kansas Entertainment
Segment Information
Ownership interest in joint venture (as a percent)	50.00%