Employee Benefit Plans (Other Pension Assumptions) (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase (average)	4.25%	4.25%
Assumed health care cost trend rate Initial trend	6.00%	6.25%
Assumed health care cost trend rate Ultimate trend	5.00%	5.00%
Assumed health care cost trend rate Year ultimate trend reached	2025	2025
Pension Plans \| Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.55%	3.30%
Interest crediting rate (average)	3.70%	3.85%
Pension Plans \| Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.10%	3.05%
Interest crediting rate (average)	4.00%	4.15%
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.40%	3.20%
Interest crediting rate (average)	1.30%	2.05%

Represents the assumed health care cost trend rate - Initial trend

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- Definition

Represents assumed health care cost trend rate - Ultimate trend

+ References

No definition available.

+ Details

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- Definition

Reprsents assumed health care cost trend rate - Year ultimate trend reached

+ References

No definition available.

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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.

+ Details

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