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Employee Benefits - Assumptions Used to Determine Benefit Obligation (Details) | Dec. 31, 2021 | Dec. 31, 2020
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Salaried VEBA |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 2.49% | 2.05%
Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 2.90% | 2.50%
Rate of compensation increase | 2.74% | 3.00%
Other Postretirement Benefits Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 2.64% |

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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=123447040&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=123447040&loc=d3e1928-114920 + Details
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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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