Facility Operating Leases (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Schedule of facility lease expense
Cash basis payment	$ 65,702	$ 66,100	$ 131,384	$ 132,299
Straight-line expense	1,456	2,161	3,182	5,297
Amortization of deferred gain	(1,093)	(1,086)	(2,186)	(2,172)
Facility lease expense	$ 66,065	$ 67,175	$ 132,380	$ 135,424