Pension and Other Postretirement Benefits - Schedule of Pension Plan Benefit Obligations (Detail) - Pension Benefits [Member] - USD ($) $ in Millions |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Defined Benefit Plan Disclosure [Line Items] | ||
| Defined benefit pension plans, Projected benefit obligation | $ 7,026 | $ 14,247 |
| Accumulated benefit obligation | 6,850 | 13,832 |
| Plan assets, Projected benefit obligation | 6,995 | 14,146 |
| Fair value of plan assets | 4,629 | 10,786 |
| Plan assets, Accumulated benefit obligation | 6,104 | 12,510 |
| Fair value of plan assets | $ 3,894 | $ 9,512 |
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- Definition For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Definition If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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