Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	$ 40,827	$ 24,741
Liabilities, fair value disclosure	(39,923)	(24,720)
Fair value, measurements, recurring | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	904
Liabilities, fair value disclosure		(9)
Fair value, measurements, recurring | Non-qualified deferred compensation assets
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	39,923	24,711
Fair value, measurements, recurring | Commodity contracts
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure		30
Fair value, measurements, recurring | Non-qualified deferred compensation liabilities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Liabilities, fair value disclosure	(39,923)	(24,711)
Level 1 | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	39,923	24,711
Liabilities, fair value disclosure	(39,923)	(24,711)
Level 1 | Fair value, measurements, recurring | Non-qualified deferred compensation liabilities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Liabilities, fair value disclosure	(39,923)	(24,711)
Level 2 | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	904	30
Liabilities, fair value disclosure	0	(9)
Level 2 | Fair value, measurements, recurring | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure	904
Liabilities, fair value disclosure		(9)
Level 2 | Fair value, measurements, recurring | Commodity contracts
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Assets, fair value disclosure		30
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent	$ 39,923	$ 24,711