Pension Benefits and Postretirement Benefits Other Than Pensions - Narrative (Details) - employees	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2021
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Number of participants and beneficiaries	3,145
Percentage of Compensation, Defined Benefit Plan Employee Contribution		3.00%
Postretirement Benefits Other than Pensions
Defined Benefit Plan Disclosure [Line Items]
Number of retired employees covered	400
Number of active employees covered	500

Defined Benefit Pension Plan, Number of Participants and Beneficiaries

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- Definition

Other Postretirement Benefit Plan, Number of Active Employees Covered

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No definition available.

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- Definition

Other Postretirement Benefit Plan, Number of Retired Employees Covered

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No definition available.

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- Definition

Percentage of Compensation, Defined Benefit Plan Employee Contribution

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No definition available.

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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.

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No definition available.

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- Details

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