Employee Benefit Plans - Schedule of Defined Benefit Plan Amounts in Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Curtailment/settlement	$ 0	$ 0
Current year actuarial (gain) loss	1,558	3,238
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Amortization of Actuarial Gain (Loss), Before Tax	222	137
Total recognized in other comprehensive (income) loss	1,336	3,101
Total recognized in net periodic benefit cost and other comprehensive (income) loss	$ 1,453	$ 4,159