Leases (Schedule of Future Minimum Lease Payments for Capital and Operating Leases) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Leases [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 185,532	[1]
Operating Leases, Future Minimum Payments, Due in Two Years	159,365	[1]
Operating Leases, Future Minimum Payments, Due in Three Years	129,121	[1]
Operating Leases, Future Minimum Payments, Due in Four Years	92,585	[1]
Operating Leases, Future Minimum Payments, Due in Five Years	63,851	[1]
Operating Leases, Future Minimum Payments, Due Thereafter	156,106	[1]
Operating Leases, Future Minimum Payments Due, Total	786,560	[1]
Capital Leases, Future Minimum Payments Due, Next Twelve Months	8,795
Capital Leases, Future Minimum Payments Due in Two Years	7,925
Capital Leases, Future Minimum Payments Due in Three Years	6,569
Capital Leases, Future Minimum Payments Due in Four Years	5,799
Capital Leases, Future Minimum Payments Due in Five Years	5,600
Capital Leases, Future Minimum Payments Due Thereafter	52,475
Capital Leases, Future Minimum Payments Due, Total	87,163
Capital Leases, Future Minimum Payments, Interest Included in Payments	(39,212)
Capital Lease Obligations, Total	47,951
Capital Lease Obligations, Current	(4,631)
Capital Lease Obligations, Noncurrent	$ 43,320

[1] Minimum lease payments have not been reduced by minimum sublease rentals due in the future of $21.0 million.