Employee Benefit Plans - Other Plan Changes Recognized in Other Comprehensive (Income) Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan [Abstract]
Net actuarial (gain) loss	$ (1,291)	$ 234	$ (166)
Amortization of prior service cost	0	0	0
Total recognized in other comprehensive (income) loss	(1,291)	234	(166)
Total Recognized in Net Periodic Benefit Cost and Other Comprehensive (Income) Loss	$ (597)	$ 471	$ 261

Amount recognized in net periodic benefit cost (credit) and other comprehensive (income) loss.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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