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Employee Benefits - Weighted Average Assumptions Used to Determine Postretirement Benefit Expense and Obligation (Detail) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Liability [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 3.30% | 4.30%
Current medical cost trend rate | 7.25% | 7.50%
Ultimate medical cost trend rate | 4.75% | 4.75%
Expense [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 4.30% | 3.70%
Current medical cost trend rate | 7.50% | 7.75%
Ultimate medical cost trend rate | 4.75% | 4.75%

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- Definition The current medical cost trend rate utilized to determine postretirement benefit expense. + 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 benefit obligation of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&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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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Details
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- Details
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