Pension and Other Postretirement Benefits (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pensions [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	$ 517,656	$ 467,641
Service cost	6,269	5,425	$ 5,961
Interest cost	15,084	18,239	17,383
Amendments	1,014	(694)
Actuarial loss	40,521	58,505
Benefits paid	(28,471)	(28,980)
Transfers in	767	2,165
Plan curtailments	(138)	0
Plan settlements	(2,165)	(1,582)
Participant contributions	1,127	1,131
Foreign exchange rate changes	6,140	1,975
Reclassified to liabilities held for sale (see Note 3)	0	(6,169)
Benefit obligation, ending balance	557,804	517,656	467,641
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	462,507	396,222
Actual return on plan assets	59,662	71,673
Company contributions	4,437	19,708
Participant contributions	1,127	1,131
Benefits paid	(28,471)	(28,980)
Plan settlements	(2,165)	(1,582)
Transfers in	767	2,165
Foreign exchange rate changes	4,914	2,170
Fair value of plan assets, ending balance	502,778	462,507	396,222
Funded/(underfunded) status, December 31	(55,026)	(55,149)
Pensions [Member] \| U.S. [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	430,625	388,334
Service cost	4,134	3,715
Interest cost	14,015	16,628
Amendments	0	240
Actuarial loss	37,709	46,662
Benefits paid	(25,049)	(24,954)
Transfers in	0	0
Plan curtailments	(138)	0
Plan settlements	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	461,296	430,625	388,334
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	380,242	322,615
Actual return on plan assets	55,813	64,681
Company contributions	2,892	17,900
Participant contributions	0	0
Benefits paid	(25,049)	(24,954)
Plan settlements	0	0
Transfers in	0	0
Foreign exchange rate changes	0	0
Fair value of plan assets, ending balance	413,898	380,242	322,615
Funded/(underfunded) status, December 31	(47,398)	(50,383)
Pensions [Member] \| Foreign Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	87,031	79,307
Service cost	2,135	1,710
Interest cost	1,069	1,611
Amendments	1,014	(934)
Actuarial loss	2,812	11,843
Benefits paid	(3,422)	(4,026)
Transfers in	767	2,165
Plan curtailments	0	0
Plan settlements	(2,165)	(1,582)
Participant contributions	1,127	1,131
Foreign exchange rate changes	6,140	1,975
Reclassified to liabilities held for sale (see Note 3)	0	(6,169)
Benefit obligation, ending balance	96,508	87,031	79,307
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	82,265	73,607
Actual return on plan assets	3,849	6,992
Company contributions	1,545	1,808
Participant contributions	1,127	1,131
Benefits paid	(3,422)	(4,026)
Plan settlements	(2,165)	(1,582)
Transfers in	767	2,165
Foreign exchange rate changes	4,914	2,170
Fair value of plan assets, ending balance	88,880	82,265	73,607
Funded/(underfunded) status, December 31	(7,628)	(4,766)
Other Postretirement Benefits [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	33,239	33,076
Service cost	81	70	85
Interest cost	1,041	1,345	1,358
Actuarial loss	950	380
Benefits paid	(3,203)	(2,917)
Participant contributions	960	1,246
Foreign exchange rate changes	36	39
Benefit obligation, ending balance	33,104	33,239	33,076
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	0	0
Company contributions	2,243	1,671
Participant contributions	960	1,246
Benefits paid	(3,203)	(2,917)
Fair value of plan assets, ending balance	0	0	$ 0
Funded/(underfunded) status, December 31	$ (33,104)	$ (33,239)

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 (increase) decrease in benefit obligation of defined benefit plan from event reducing expected years of future service of present employees or eliminating accrual of benefits for some or all future services of present employees.

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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 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 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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