Fair Value Measurements - Levels of Inputs Used to Measure Fair Value of Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
U.S. non-qualified deferred compensation plan	$ 12,729	$ 11,401
Assets designated for retirement and pension plans	24,700	24,096
Derivative designated as cash flow hedge	119
Derivatives designated as fair value hedges	(30)	(70)
Warrants and equity securities	453	501
Acquisition earnout accruals	(11,518)	(10,270)
Total fair value of assets	26,453	25,658
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
U.S. non-qualified deferred compensation plan	12,729	11,401
Assets designated for retirement and pension plans
Derivative designated as cash flow hedge
Derivatives designated as fair value hedges
Warrants and equity securities
Acquisition earnout accruals
Total fair value of assets	12,729	11,401
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
U.S. non-qualified deferred compensation plan
Assets designated for retirement and pension plans	24,700	24,096
Derivative designated as cash flow hedge	119
Derivatives designated as fair value hedges	(30)	(70)
Warrants and equity securities
Acquisition earnout accruals
Total fair value of assets	24,789	24,026
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
U.S. non-qualified deferred compensation plan
Assets designated for retirement and pension plans
Derivative designated as cash flow hedge
Derivatives designated as fair value hedges
Warrants and equity securities	453	501
Acquisition earnout accruals	(11,518)	(10,270)
Total fair value of assets	$ (11,065)	$ (9,769)