Retirement Benefits (Weighted-Average Assumptions Used In Calculating The Benefit Obligations For All Plans) (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.24%	3.11%
Rate of compensation increase	3.00%	3.00%
Expected rate of return on plan assets	6.72%	7.33%
Interest Crediting Rate	3.82%	3.82%
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	1.99%	2.93%
Rate of compensation increase	3.00%	3.00%
Expected rate of return on plan assets	6.60%	7.00%
Interest Crediting Rate	0.87%	1.81%

Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Of Expected Rate Of Return On Plan Assets

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Weighted-average interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(4)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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