Fair Value Measurements (Details) (Fair value, measurements, recurring, USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	$ 41,797	$ 24,741
Liabilities, fair value disclosure	(48,976)	(24,720)
Non-qualified deferred compensation assets
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	41,797	24,711
Commodity contracts
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure		30
Liabilities, fair value disclosure	(4,609)
Foreign currency contracts
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Liabilities, fair value disclosure	(2,570)	(9)
Non-qualified deferred compensation liabilities
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Liabilities, fair value disclosure	(41,797)	(24,711)
Level 1
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	41,797	24,711
Liabilities, fair value disclosure	(41,797)	(24,711)
Level 1 | Non-qualified deferred compensation assets
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	41,797	24,711
Level 1 | Non-qualified deferred compensation liabilities
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Liabilities, fair value disclosure	(41,797)	(24,711)
Level 2
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	0	30
Liabilities, fair value disclosure	(7,179)	(9)
Level 2 | Non-qualified deferred compensation assets
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	0
Level 2 | Commodity contracts
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, fair value disclosure		30
Liabilities, fair value disclosure	(4,609)
Level 2 | Foreign currency contracts
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Liabilities, fair value disclosure	$ (2,570)	$ (9)