Pensions and Postretirement Benefits Other than Pensions - Estimated Benefit Payments for Domestic and Foreign Pension Plans and Other Postretirement Benefit Plans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Pension Benefits - All Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	$ 80,300
2016	78,400
2017	79,700
2018	80,600
2019	81,700
2020 through 2024	425,800
Other Postretirement Benefits - All Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	14,600
2016	15,000
2017	15,400
2018	15,600
2019	16,000
2020 through 2024	$ 82,900