Benefit Plan Schedule of assumptions used to determine benefit obligations (Details)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.00%	3.53%	4.60%
Rate of compensation increase
Under age 30 [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	8.25%	10.00%	10.00%
Ages 30-39 [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	6.00%	6.00%	6.00%
Ages 40-49 [Domain]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.00%	4.00%	4.00%
Ages 50 to 54 [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	4.25%	3.00%	3.00%
Ages 55-59
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.75%	3.00%	3.00%
Ages 60-64
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.50%	3.00%	3.00%
Ages 65 and over
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.25%	3.00%	3.00%

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

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

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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