Defined Benefit Plan, Actuarial Gain (Loss), Decrease In Weighted Average Discount Rate

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- Definition

Defined Benefit Plan, Plan Amendment, Elimination of Benefits, Maximum Age

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- Definition

Defined Benefit Plan, Plan Amendment, Elimination of Benefits, Minimum Age

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- Definition

Target allocation percentage of investments in within which plan assets investment are managed.

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- Definition

Amount recognized in net periodic benefit cost (credit) and other comprehensive (income) loss.

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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

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Employee Benefit Plans - Narrative (Details) - USD ($)			12 Months Ended
Employee Benefit Plans - Narrative (Details) - USD ($)	Jan. 01, 2020	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			$ 0	$ 0	$ 0
Expected contributions in the next fiscal year			$ 0
Percentage within which the planned allocation is managed			5.00%
Investments at fair value			$ 3,000,000,000	2,825,000,000
Growth-Oriented
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of pension plan assets			60.00%
Investments at fair value			$ 1,816,000,000	2,027,000,000
Immunizing
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of pension plan assets			40.00%
Investments at fair value			$ 1,184,000,000	798,000,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial losses (gains)			$ 197,000,000	418,000,000
Decrease in weighted average discount rate			0.70%
Investments at fair value			$ 3,000,000,000	2,825,000,000	2,431,000,000
Pre-tax (loss) gain to be amortized related to post-retirement obligations			(854,000,000)
Expense associated with savings plans			39,000,000	41,000,000	41,000,000
Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Life insurance and contributions to the medical program for eligible retirees will be eliminated (younger than)		65 years
Life insurance and contributions to the medical program for eligible retirees will be eliminated (65 years or older)	65 years
Decrease in post-retirement benefit liability as result of plan amendments					102,000,000
Net actuarial losses (gains)			(11,000,000)	$ 22,000,000
Decrease in weighted average discount rate				1.11%
Investments at fair value			0	$ 0	0
Pre-tax (loss) gain to be amortized related to post-retirement obligations			78,000,000
Premium expense incurred under the plan			$ 20,000,000	$ 26,000,000	30,000,000
Post-retirement Benefits \| Pension and Other Post-Employment Benefits
Defined Benefit Plan Disclosure [Line Items]
Gain on decrease in post-retirement benefit liability due to plan amendments recognized in other comprehensive income					$ 102,000,000