Pension and Postretirement Benefits (Funded Status) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Postretirement Medical Benefits
Funded status of plan:
Benefit Obligation	$ (18,862)	$ (18,810)	$ (23,882)
Funded status	(18,862)	(18,810)
United States \| Pension Plan
Funded status of plan:
Plan assets, at fair value	482,553	425,792	464,779
Benefit Obligation	(471,462)	(432,595)	(461,355)
Funded status	11,091	(6,803)
Foreign Plan \| Pension Plan
Funded status of plan:
Plan assets, at fair value	262,559	232,175	248,733
Benefit Obligation	(425,617)	(376,649)	$ (413,960)
Funded status	$ (163,058)	$ (144,474)

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

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.

+ References

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- Definition

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.

+ References

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- References

No definition available.

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