Debt (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Debt Disclosure [Abstract]
Notional Amount of Interest Rate Fair Value Hedge Derivatives	$ 500,000,000	$ 400,000,000
Short-term debt and current portion of long-term debt:
Short-term debt, Weighted Average Interest Rate	1.02%	1.70%
Short-term debt	1,590,000	1,315,000
Current portion of long-term debt, including capital leases	399,256,000	258,123,000
Total short-term debt and current portion of long-term debt	$ 400,846,000	$ 259,438,000