Accounts Receivable (Company's Accounts Receivable And Securitized Accounts Receivable) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Accounts Receivable [Abstract]
Gross domestic accounts receivable	$ 82,296	$ 84,087
Gross securitized accounts receivable	341,000	280,000
Gross foreign receivables	535,256	413,019
Total gross receivables	958,552	777,106
Less allowance for doubtful accounts	(17,742)	(15,315)	(15,187)	(14,256)
Net accounts and securitized accounts receivable	$ 940,810	$ 761,791