Employee Benefits - Assumptions Used in Computation of Net Periodic Pension Expense (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Weighted-average discount rate	1.28%	1.81%	1.78%
Expected return on plan assets	2.04%	2.54%	2.45%
Average compensation increase	2.58%	2.58%	2.66%
Cash balance interest credit rate	1.20%	1.90%	1.90%

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

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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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- References

No definition available.

+ Details

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