Pensions and Postretirement Benefits Other than Pensions - Components of Net Periodic Benefit Costs (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Amortization of actuarial loss	$ (11,719)
Pension Benefits - Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2,759	2,440
Interest cost	10,050	10,711
Expected return on plan assets	(13,665)	(13,135)
Amortization of actuarial loss	9,879	7,005
Net periodic benefit cost	9,023	7,021
Pension Benefits - International [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	3
Interest cost	4,040	4,926
Expected return on plan assets	(3,165)	(5,015)
Amortization of actuarial loss	1,840	2,122
Net periodic benefit cost	2,718	2,036
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	628	601
Interest cost	2,580	2,826
Amortization of prior service cost	(141)	(142)
Net periodic benefit cost	$ 3,067	$ 3,285