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Leases (Narrative) (Details) - BuildingLease	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating leases term description	The Company is obligated under a number of non-cancellable operating lease agreements for land, buildings and equipment with terms, including renewal options reasonably certain to be exercised, extending through 2061
Sublease extension terms	One building lease was subleased with terms that extended through June 30, 2021
Number of buildings subleased		1
Operating leases, weighted average remaining lease term	24 years
Operating leases, weighted-average discount rate	3.71%

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- Definition

Number of buildings subleased.

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- Definition

Description of lessee's operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

Description of terms and conditions of option to extend operating sublease.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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