Employee Benefit Plans - Components of Net Periodic Pension Costs and Estimated Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
U.S. Plans
Components of net periodic pension costs of the plans
Service cost	$ 957	$ 1,136	$ 895
Interest cost	4,589	4,499	4,815
Expected return on plan assets	(6,040)	(7,070)	(7,541)
Amortization of prior service cost		15	74
Net actuarial loss amortization	3,010	2,606	877
Settlement	1,149	607	1,025
Net periodic pension cost (benefit)	3,665	1,793	145
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss)
Current year actuarial (loss) gain	(4,112)	(3,348)	(19,756)
Amortization of actuarial loss	3,010	2,606	877
Amortization of prior service cost		15	74
Settlement	1,149	607	1,025
Total recognized in other comprehensive income (loss)	47	(120)	(17,780)
Total recognized in net periodic pension cost and other comprehensive income (loss)	(3,618)	(1,913)	(17,925)
Estimated amounts that will be amortized from accumulated other comprehensive income (loss) into net periodic pension cost
Net actuarial loss	2,984
Estimated amounts that will be amortized from accumulated other comprehensive income into net periodic pension cost	2,984
European Plans
Components of net periodic pension costs of the plans
Service cost	395	288	342
Interest cost	1,142	1,250	1,653
Expected return on plan assets	(1,416)	(1,705)	(1,549)
Net actuarial loss amortization	229	219	245
Settlement	361	199
Net periodic pension cost (benefit)	711	251	691
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss)
Current year actuarial (loss) gain	(4,222)	(984)	(2,117)
Amortization of actuarial loss	229	219	245
Current year prior service credit	91
Settlement	361	199
Foreign currency exchange	1,122	603	818
Total recognized in other comprehensive income (loss)	(2,419)	37	(1,054)
Total recognized in net periodic pension cost and other comprehensive income (loss)	(3,130)	$ (214)	$ (1,745)
Estimated amounts that will be amortized from accumulated other comprehensive income (loss) into net periodic pension cost
Prior service credit	(9)
Net actuarial loss	424
Estimated amounts that will be amortized from accumulated other comprehensive income into net periodic pension cost	$ 415