Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified			12 Months Ended			12 Months Ended			12 Months Ended			12 Months Ended		12 Months Ended					1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 4.75% Senior Notes	Dec. 31, 2012 4.75% Senior Notes	Nov. 30, 2009 4.75% Senior Notes	Dec. 31, 2013 4.00% Senior Notes	Dec. 31, 2012 4.00% Senior Notes	Jan. 31, 2012 4.00% Senior Notes	Dec. 31, 2013 Revolving Credit Facility	Dec. 31, 2012 Revolving Credit Facility	Jul. 31, 2013 Revolving Credit Facility	Dec. 31, 2013 Credit Agreement	Oct. 31, 2013 Credit Agreement	Dec. 31, 2013 Receivables Securitization Facility	Dec. 31, 2012 Receivables Securitization Facility	Dec. 31, 2011 Receivables Securitization Facility	Dec. 31, 2013 Notes payable to foreign banks and other debt	Dec. 31, 2012 Notes payable to foreign banks and other debt	Jan. 31, 2014 2.55% Senior Notes Subsequent Event
Debt
Debt	$ 2,132,874	$ 1,706,497	$ 599,813	$ 599,589		$ 498,973	$ 498,846		$ 927,300	$ 500,400		$ 100,000			$ 100,000		$ 6,788	$ 7,662
Less current portion	701,437	100,293
Total long-term debt	1,431,437	1,606,204
Average Interest Rate (as a percent)			4.75%	4.75%		4.00%	4.00%		1.50%	1.52%		1.16%			0.86%		4.76%	8.45%
Unamortized discount			187	411		1,027	1,154
Increase in commitment under the Revolving Credit Facility											500,000
Commitment under the Revolving Credit Facility											1,500,000
Uncommitted Line of Credit													100,000
Borrowings under the Revolving Credit Facility									927,300
Borrowings Under Uncommitted Line of Credit												100,000
Availability under the Revolving Credit Facility									572,700
Interest rate on borrowings under the Revolving Credit Facility, variable rate									LIBOR			LIBOR
Debt instrument, principal amount					600,000			500,000											750,000
Stated interest rate (as a percent)			4.75%	4.75%	4.75%	4.00%	4.00%	4.00%											2.55%
Redemption price as a percentage of principal amount						100.00%													100.00%
Debt instrument, face amount, net of discount (as a percent)					99.813%			99.746%											99.846%
Debt instrument, fair value			621,000	640,000		491,000	533,000
Maximum amount of undivided interest														100,000
Fees payable under credit facility														900	1,000	1,600
Maturity of the Company's long-term debt over each of the next five years
2014	701,437
2015	953
2016	772
2017	394
2018	928,675
Thereafter	500,643
Long-term debt including current portion	2,132,874	1,706,497	599,813	599,589		498,973	498,846		927,300	500,400		100,000			100,000		6,788	7,662
Issued and unused letters of credit	$ 14,100