Summary of Significant Accounting Policies (Property and Equipment, Including Original Useful Lives) (Details) (USD $) In Thousands, unless otherwise specified			12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Building and Building Improvements [Member]	Dec. 31, 2011 Leasehold Improvements [Member]	Dec. 31, 2011 Furniture, Fixtures and Equipment [Member]	Dec. 31, 2011 Vehicles [Member]
Land	$ 462,790	$ 392,600
Buildings and building improvements	1,012,709	921,929
Leasehold improvements	395,274	370,018
Furniture, fixtures, and equipment	906,257	777,485
Vehicles	206,685	182,942
Construction in progress	43,281	60,460
Total property and equipment	3,026,996	2,705,434
Less: accumulated depreciation and amortization	933,229	775,339
Net property and equipment	$ 2,093,767	$ 1,930,095
Property, plant and equipment, minimum useful life, in years			15	3	3	5
Property, plant and equipment, maximum useful life, in years			39	25	20	10