Pension and Postretirement Benefits - Summary of Funded Status of the Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Funded Plans
Change in benefit obligation:
Benefit obligation at beginning of year	$ 14,906	$ 16,012
Interest cost	629	616
Recognized net actuarial loss	240	(1,013)
Benefits paid	(748)	(709)
Benefit obligation at end of year	15,027	14,906	$ 16,012
Change in plan assets:
Fair value of plan assets at beginning of year	10,479	11,198
Actual return on plan assets	273	(742)
Company contributions	412	732
Benefits paid	(748)	(709)
Fair value of plan assets at end of year	10,416	10,479	11,198
Funded status at end of year	(4,611)	(4,427)
Unfunded Pension Plans
Change in benefit obligation:
Benefit obligation at beginning of year	10,049	11,127
Service cost	97	101
Interest cost	403	402
Recognized net actuarial loss	(221)	(1,072)
Benefits paid	(503)	(509)
Benefit obligation at end of year	9,825	10,049	11,127
Change in plan assets:
Company contributions	503	509
Benefits paid	(503)	(509)
Funded status at end of year	(9,825)	(10,049)
Postretirement Benefit Plans
Change in benefit obligation:
Benefit obligation at beginning of year	14,573	16,235
Service cost	99	152
Interest cost	573	619
Recognized net actuarial loss	(790)	(1,248)
Plan amendments	73	3
Benefits paid	(909)	(1,188)
Benefit obligation at end of year	13,619	14,573	16,235
Change in plan assets:
Company contributions	909	1,188
Benefits paid	(909)	(1,188)
Funded status at end of year	(13,619)	(14,573)
Foreign Pension Plans
Change in benefit obligation:
Service cost	488	503	413
Interest cost	488	505	631
Recognized net actuarial loss	162	160	145
Change in plan assets:
Fair value of plan assets at beginning of year	9,705
Fair value of plan assets at end of year	10,576	9,705
Foreign Pension Plans | Funded Plans
Change in benefit obligation:
Benefit obligation at beginning of year	9,744	12,016
Service cost	488	503
Interest cost	400	415
Recognized net actuarial loss	395	(176)
Benefits paid	(818)	(1,115)
Benefit obligation at end of year	10,488	9,744	12,016
Translation adjustment	279	(1,899)
Change in plan assets:
Fair value of plan assets at beginning of year	9,705	11,747
Actual return on plan assets	617	377
Company contributions	795	566
Benefits paid	(818)	(1,115)
Translation adjustment	277	(1,870)
Fair value of plan assets at end of year	10,576	9,705	11,747
Funded status at end of year	88	(39)
Foreign Pension Plans | Unfunded Pension Plans
Change in benefit obligation:
Benefit obligation at beginning of year	2,470	2,756
Interest cost	87	89
Recognized net actuarial loss	105	178
Benefits paid	(177)	(179)
Benefit obligation at end of year	2,486	2,470	$ 2,756
Translation adjustment	1	(374)
Change in plan assets:
Company contributions	177	179
Benefits paid	(177)	(179)
Funded status at end of year	$ (2,486)	$ (2,470)