Defined Benefit Plan,Vesting Period

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- Definition

Defined Contribution Plan, Vesting Period

+ References

No definition available.

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- Definition

defined benefit plan covered employee percentage

+ References

No definition available.

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- Definition

Purchase of Medical Coverage through Medicare Exchange Participant, Age

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

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- References

No definition available.

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- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
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-Publisher FASB
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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

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- References

No definition available.

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- Definition

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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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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-Publisher FASB
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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- References

No definition available.

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Share-based Compensation and Employee Benefits - Pensions and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Savings plan - defined contribution plan
Pension and Other Postretirement Benefit Plans
Percentage of eligible compensation contributed	5.00%
Plan vesting period	2 years
Plan cost	$ 53	$ 50	$ 48
Pension Benefits
Pension and Other Postretirement Benefit Plans
Percentage of employees covered	100.00%
Vesting period	3 years
Accumulated benefit obligation	$ 2,804	2,659
Expected Payment of Future Benefits and Employer Contributions
Expected employer contributions in next year	$ 56
Pension Benefits \| Minimum \| Equities
Plan Assets
Target allocation percentage	31.00%
Pension Benefits \| Minimum \| Fixed Income Securities
Plan Assets
Target allocation percentage	37.00%
Pension Benefits \| Minimum \| Cash
Plan Assets
Target allocation percentage	0.00%
Pension Benefits \| Minimum \| Alternative Investments
Plan Assets
Target allocation percentage	0.00%
Pension Benefits \| Minimum \| Company Securities
Plan Assets
Target allocation percentage	0.00%
Pension Benefits \| Maximum \| Equities
Plan Assets
Target allocation percentage	55.00%
Pension Benefits \| Maximum \| Fixed Income Securities
Plan Assets
Target allocation percentage	57.00%
Pension Benefits \| Maximum \| Cash
Plan Assets
Target allocation percentage	5.00%
Pension Benefits \| Maximum \| Alternative Investments
Plan Assets
Target allocation percentage	2.00%
Pension Benefits \| Maximum \| Company Securities
Plan Assets
Target allocation percentage	10.00%
OPEB
Pension and Other Postretirement Benefit Plans
Medicare participation, age	65
Accumulated benefit obligation whose accumulated benefit obligations exceeded the fair value of plan assets	$ 255	288
Accumulated benefit obligation whose accumulated benefit obligations exceeded the fair value of plan assets, fair value of plan assets	48	$ 57
Expected Payment of Future Benefits and Employer Contributions
Expected employer contributions in next year	$ 7
Actuarial Assumptions and Sensitivity Analysis
Weighted-average annual rate of increase in the per capita cost of covered health care benefits	5.80%
Ultimate health care cost trend rate	4.50%
OPEB \| Minimum \| Equities
Plan Assets
Target allocation percentage	46.00%
OPEB \| Minimum \| Fixed Income Securities
Plan Assets
Target allocation percentage	25.00%
OPEB \| Minimum \| Cash
Plan Assets
Target allocation percentage	0.00%
OPEB \| Maximum \| Equities
Plan Assets
Target allocation percentage	68.00%
OPEB \| Maximum \| Fixed Income Securities
Plan Assets
Target allocation percentage	50.00%
OPEB \| Maximum \| Cash
Plan Assets
Target allocation percentage	22.00%