Pension and Other Postretirement Benefits (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pensions [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	$ 467,641	$ 498,110
Service cost	5,425	5,961	$ 6,055
Interest cost	18,239	17,383	18,819
Amendments	(694)	826
Actuarial loss (gain)	58,505	(24,449)
Benefits paid	(28,980)	(31,614)
Transfers in	2,165	3,462
Plan Settlement	(1,582)	0
Participant contributions	1,131	1,120
Foreign exchange rate changes	1,975	(3,158)
Reclassified to liabilities held for sale (see Note 3)	(6,169)	0
Benefit obligation, ending balance	517,656	467,641	498,110
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	396,222	454,438
Actual return on plan assets	71,673	(32,609)
Company contributions	19,708	4,732
Participant contributions	1,131	1,120
Benefits paid	(28,980)	(31,614)
Plan Settlements	(1,582)	0
Transfers in	2,165	3,462
Foreign exchange rate changes	2,170	(3,307)
Fair value of plan assets, ending balance	462,507	396,222	454,438
Funded/(underfunded) status, December 31	(55,149)	(71,419)
Pensions [Member] \| U.S. [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	388,334	415,369
Service cost	3,715	4,290
Interest cost	16,628	15,875
Amendments	240	0
Actuarial loss (gain)	46,662	(22,193)
Benefits paid	(24,954)	(25,007)
Transfers in	0	0
Plan Settlement	0	0
Participant contributions	0	0
Foreign exchange rate changes	0	0
Reclassified to liabilities held for sale (see Note 3)	0	0
Benefit obligation, ending balance	430,625	388,334	415,369
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	322,615	375,378
Actual return on plan assets	64,681	(30,681)
Company contributions	17,900	2,925
Participant contributions	0	0
Benefits paid	(24,954)	(25,007)
Plan Settlements	0	0
Transfers in	0	0
Foreign exchange rate changes	0	0
Fair value of plan assets, ending balance	380,242	322,615	375,378
Funded/(underfunded) status, December 31	(50,383)	(65,719)
Pensions [Member] \| Foreign Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	79,307	82,741
Service cost	1,710	1,671
Interest cost	1,611	1,508
Amendments	(934)	826
Actuarial loss (gain)	11,843	(2,256)
Benefits paid	(4,026)	(6,607)
Transfers in	2,165	3,462
Plan Settlement	(1,582)	0
Participant contributions	1,131	1,120
Foreign exchange rate changes	1,975	(3,158)
Reclassified to liabilities held for sale (see Note 3)	(6,169)	0
Benefit obligation, ending balance	87,031	79,307	82,741
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	73,607	79,060
Actual return on plan assets	6,992	(1,928)
Company contributions	1,808	1,807
Participant contributions	1,131	1,120
Benefits paid	(4,026)	(6,607)
Plan Settlements	(1,582)	0
Transfers in	2,165	3,462
Foreign exchange rate changes	2,170	(3,307)
Fair value of plan assets, ending balance	82,265	73,607	79,060
Funded/(underfunded) status, December 31	(4,766)	(5,700)
Other Postretirement Benefits [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	33,076	37,570
Service cost	70	85	83
Interest cost	1,345	1,358	1,561
Actuarial loss (gain)	380	(3,791)
Benefits paid	(2,917)	(3,435)
Participant contributions	1,246	1,280
Foreign exchange rate changes	39	9
Benefit obligation, ending balance	33,239	33,076	37,570
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	0	0
Company contributions	1,671	2,155
Participant contributions	1,246	1,280
Benefits paid	(2,917)	(3,435)
Fair value of plan assets, ending balance	0	0	$ 0
Funded/(underfunded) status, December 31	$ (33,239)	$ (33,076)

Defined Benefit Plan, Transfers In, Benefit Obligation

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of decrease in benefit obligation of defined benefit plan from disposal or classification as held-for-sale.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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