Employee Benefit Plans - Changes Recognized in OCI (Details) - Defined benefit plans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Actuarial gain/(loss)	$ (7,765)	$ 12,205	$ (9,379)
Amortization of actuarial loss	(3,527)	(4,424)	(4,406)
Prior service cost	(424)	0	0
Settlement losses	(11,713)	0	0
Total	$ 7,051	$ 16,629	$ (4,973)

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Amount, before tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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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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