Goodwill and Other Intangibles (Amortizable Intangibles) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Amortizable intangible assets, cost	$ 51,627	$ 52,453
Amortizable intangible assets, accumulated amortization expense	(27,884)	(24,396)
Favorable Leases [Member]
Amortizable intangible assets, cost	50,910	51,660
Amortizable intangible assets, accumulated amortization expense	(27,468)	(23,969)
Noncompete Agreements [Member]
Amortizable intangible assets, cost	717	793
Amortizable intangible assets, accumulated amortization expense	(416)	(427)
Unfavorable Leases [Member]
Amortizable intangibles, cost	49,380	49,380
Amortizable intangibles, accumulated amortization benefit	$ 30,870	$ 26,560