Pension and Postretirement Benefits other than Pensions - Net Periodic Benefit Cost of Defined Benefit Plans and Other Postretirement Benefit Plans (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
U.S. Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	$ 232	$ 213	$ 696	$ 639
Interest cost	3,084	3,370	9,252	10,110
Expected return on plan assets	(4,421)	(4,764)	(13,263)	(14,292)
Amortization of prior service cost (credit) and recognized actuarial loss (gain)	276	16	828	48
Other	0	0	0	0
Net periodic benefit cost (income)	(829)	(1,165)	(2,487)	(3,495)
Non-U.S. Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	868	843	2,633	2,571
Interest cost	1,261	1,775	3,845	5,389
Expected return on plan assets	(830)	(970)	(2,559)	(2,900)
Amortization of prior service cost (credit) and recognized actuarial loss (gain)	665	222	2,012	683
Other	114	0	355	0
Net periodic benefit cost (income)	2,078	1,870	6,286	5,743
U.S. Other Postretirement Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	109	106	327	318
Interest cost	353	397	1,059	1,191
Amortization of prior service cost (credit) and recognized actuarial loss (gain)	(396)	(481)	(1,188)	(1,443)
Other	6	6	18	18
Net periodic benefit cost (income)	72	28	216	84
Non-U.S. Other Postretirement Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	93	138	290	412
Interest cost	165	191	516	569
Amortization of prior service cost (credit) and recognized actuarial loss (gain)	(5)	(73)	(15)	(217)
Other	0	0	0	0
Net periodic benefit cost (income)	$ 253	$ 256	$ 791	$ 764