Employee Benefit Plans - Reconciliation of Changes in Fair Value of Plan Assets (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Employer contributions	$ 600,000
Non-U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	71,286,000	$ 75,855,000
Actual return on plan assets	5,594,000	9,371,000
Employer contributions	651,000	2,832,000	$ 2,200,000
Benefits paid	(2,836,000)	(3,515,000)
Plan participants’ contributions	0	307,000
Settlement and curtailment	(4,597,000)	0
Foreign exchange rate changes	7,043,000	(13,564,000)
Fair value of plan assets at end of year	77,141,000	71,286,000	75,855,000
U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	171,240,000	167,947,000
Actual return on plan assets	24,760,000	8,657,000
Employer contributions	2,348,000	383,000	500,000
Benefits paid	(6,795,000)	(5,747,000)
Plan participants’ contributions	0	0
Settlement and curtailment	(2,313,000)	0
Foreign exchange rate changes	0	0
Fair value of plan assets at end of year	$ 189,240,000	$ 171,240,000	$ 167,947,000