Facility Operating Leases (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Facility Operating Leases [Abstract]
Cash basis payment	$ 70,157	$ 65,702	$ 141,053	$ 131,384
Straight-line expense	1,564	1,456	3,206	3,182
Amortization of deferred gain	(1,093)	(1,093)	(2,186)	(2,186)
Facility lease expense	$ 70,628	$ 66,065	$ 142,073	$ 132,380

Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

No definition available.

Name:	us-gaap_LeaseAndRentalExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration