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Employee Benefit Plans and Other Postretirement Benefits - Fair Value Measurements of Plan Assets (Parenthetical) (Details) - Private Equity Securities - Significant unobservable input (Level 3) $ in Millions | Dec. 31, 2020 USD ($)
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Investment commitment | $ 15.0
Unfunded portion of investment commitment | $ 2.0

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- Definition Commitment to invest in private equity securities. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Unfunded portion of commitment to invest in private equity securities. + References No definition available. + Details
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Balance Type: | debit
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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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- Details
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- Details
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