Benefit Plans, Weighted Average Assumptions Used to Determine Benefit Obligations (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Postretirement Benefit Plans [Abstract]
Eligible age for several postretirement benefit plans	55 years
Eligible age for Medicare benefits	65 years
Pension Benefits [Member]
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.10%	3.00%	4.10%
Interest crediting rate	3.00%	3.70%	3.80%
Pension Benefits [Member] \| Minimum [Member]
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	0.00%	3.00%	3.90%
Pension Benefits [Member] \| Maximum [Member]
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	3.00%	5.50%	5.50%
Other Postretirement Benefits [Member]
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.20%	3.00%	4.10%

Eligible age for several postretirement benefit plans.

No definition available.

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- Definition

Eligible age for Medicare benefits.

+ References

No definition available.

+ Details

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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

+ Details

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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

+ Details

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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

+ Details

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- References

No definition available.

+ Details

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- References

No definition available.

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- Details

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