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Employee Benefits - Fair Value Measurements of Investments Held by Retirement Plan (Parenthetical) (Detail) | Dec. 31, 2021 Stock Fund
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Large-Cap Value | Minimum | Common/Collective Trusts - Equity |
Defined Benefit Plan Disclosure [Line Items] |
Number of stocks held | 60
Large-Cap Value | Maximum | Common/Collective Trusts - Equity |
Defined Benefit Plan Disclosure [Line Items] |
Number of stocks held | 70
Small-Cap Core | Equity Funds |
Defined Benefit Plan Disclosure [Line Items] |
Mutual fund investment in marketable securities with percentage of market capitalization | 10.00%
International Equity | Minimum | Equity Funds |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of investments | 80.00%
U.S. Core | Fixed Income Funds |
Defined Benefit Plan Disclosure [Line Items] |
Number of mutual funds | Fund | 3
U.S. Core | Fixed Income Funds | Mortgage-backed Securities |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of investments | 50.00%
U.S. Core | Minimum | Fixed Income Funds | Fixed Income Securities |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of investments | 80.00%

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