Operating Leases (Rent Expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Rent expense	$ 119,674	$ 114,394	$ 117,565
Leased Facilities [Member]
Rent expense	95,808	92,854	91,270
Leased Vehicles [Member]
Rent expense	$ 23,866	$ 21,540	$ 26,295

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