Retirement Benefits (Schedule of Rollforward of Level 3 Assets) (Details) - Pension Plan - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 33,915	$ 30,399
Sales	(669)	(616)
Gains (losses) included in earnings	(1,166)	4,132
Exchange rate effect	(2,346)	0
Ending balance	29,734	33,915
Guaranteed Deposits
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	33,733	30,155
Sales	(669)	(616)
Gains (losses) included in earnings	(1,140)	4,194
Exchange rate effect	(2,346)	0
Ending balance	29,578	33,733
Commingled funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	182	244
Sales	0	0
Gains (losses) included in earnings	(26)	(62)
Exchange rate effect	0	0
Ending balance	$ 156	$ 182

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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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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