Commitments and Contingencies (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Mar. 21, 2011 claim	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Commitments And Contingencies [Line Items]
Rent expense under operating leases		$ 116,541	$ 97,587	$ 103,416
Document Fiscal Year Focus		2013
Loss Contingency, New Claims Filed, Number	2
Loss Contingency, Damages Sought, Multiple	3
Standby Letters of Credit Related to Various Insurance Contracts and Foreign Vendor Commitments [Member] | Senior Secured Credit Facility [Member]
Commitments And Contingencies [Line Items]
Standby letters of credit for various insurance contracts and commitments to foreign vendors		$ 47,713	$ 50,540
Maximum [Member] | Standby Letters of Credit Related to Various Insurance Contracts and Foreign Vendor Commitments [Member] | Senior Secured Credit Facility [Member]
Commitments And Contingencies [Line Items]
Expiration period for standby letters of credit		2 years