Employee Benefits - Schedule of Assumptions Used in Calculation Net Periodic Benefit Cost (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Benefits
Weighted average assumptions used to determine the net periodic benefit cost
Discount Rate	3.36%	4.41%	3.90%
Expected Long-Term Rate of Return on Plan Assets	5.75%	5.75%	5.75%
Health Care Cost Trend Rate	0.00%	0.00%	0.00%
Postretirement Benefits
Weighted average assumptions used to determine the net periodic benefit cost
Discount Rate	3.42%	4.48%	3.96%
Expected Long-Term Rate of Return on Plan Assets	0.00%	0.00%	0.00%
Health Care Cost Trend Rate	5.70%	6.00%	6.30%

The assumed health care cost trend rate to calculate net periodic benefit cost.

No definition available.

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- Definition

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

+ References

+ Details

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost 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)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2919-114920

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- References

No definition available.

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- Details

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- Details

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