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Employee Benefit Plans (The Weighted-Average Discount Rate Assumptions Used to Determine Net Periodic Benefit Costs) (Detail) - Unfunded Supplemental Benefit Plans | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Discount rates: |  |  |
Projected benefit obligation | 2.49% | 3.27% | 4.32%
Service cost | 3.14% | 3.71% | 4.55%
Interest cost | 1.83% | 2.86% | 4.00%

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- Definition Defined benefit plan assumptions used calculating net periodic benefit cost discount rate for interest cost. + References No definition available. + Details
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- Definition Defined benefit plan assumptions used calculating net periodic benefit cost discount rate for service cost. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost 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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- References No definition available. + Details
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- Details
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