Employee Benefits - Pension and Other Defined Contribution Retirement Plan Expenses (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Pension Plans [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned	$ 698	$ 772	$ 1,395	$ 1,543
Interest cost on projected benefit obligation	4,561	6,006	9,122	12,013
Expected return on plan assets	(9,246)	(8,070)	(18,492)	(16,139)
Net amortization and deferrals	1,793	1,385	3,585	2,772
Total postretirement benefit income	(2,194)	93	(4,390)	189
Total expense	330	2,304	389	4,801
Pension Plans [Member] | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned	5,610	3,863	11,220	7,638
Interest cost on projected benefit obligation	3,911	6,372	7,822	12,737
Expected return on plan assets	(12,334)	(11,985)	(24,668)	(23,934)
Net amortization and deferrals	3,988	3,286	7,977	6,550
Total postretirement benefit income	1,175	1,536	2,351	2,991
Total expense	2,791	3,299	5,264	6,461
Defined Contribution and Other Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned	221	214	442	429
Interest cost on projected benefit obligation	588	787	1,176	1,574
Net amortization and deferrals	(1,046)	(1,355)	(2,092)	(2,710)
Total postretirement benefit income	(237)	(354)	(474)	(707)
Defined Contribution and Other Retirement Plans [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined contribution and other retirement plans	2,524	2,211	4,779	4,612
Defined Contribution and Other Retirement Plans [Member] | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined contribution and other retirement plans	$ 1,616	$ 1,763	$ 2,913	$ 3,470