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- Definition

defined benefit plan covered employee percentage

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- Definition

Other Postretirement Benefit Plans [Abstract]

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- Definition

Pension Plans [Abstract]

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- Definition

Purchase of Medical Coverage through Medicare Exchange Participant, Age

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- Definition

Savings Plan [Abstract]

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No definition available.

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- Definition

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

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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- Definition

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

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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.

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- References

No definition available.

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

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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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- 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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- Definition

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

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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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Share-based Compensation and Employee Benefits (Pensions and Other Postretirement Benefit Plans - Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components of Accumulated Other Comprehensive Income/Loss
Expected amortization in next year	$ 40
Expected amortization in next year, unrecognized net actuarial loss	(42)
Expected amortization in next year, unrecognized prior service (credit)	$ (2)
Pension Benefits [Member]
Pension Plans and OPEB
Percentage of employees covered	100.00%
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ 27	$ 39	$ 10
Components of Accumulated Other Comprehensive Income/Loss
Accumulated benefit obligation	2,535	2,840
Expected Payment of Future Benefits and Employer Contributions
Expected employer contributions in next year	$ 60
Pension Benefits [Member] \| Minimum [Member] \| Equity Securities [Member]
Plan Assets
Target allocation percentage	34.00%
Pension Benefits [Member] \| Minimum [Member] \| Fixed Income Securities [Member]
Plan Assets
Target allocation percentage	37.00%
Pension Benefits [Member] \| Minimum [Member] \| Cash [Member]
Plan Assets
Target allocation percentage	0.00%
Pension Benefits [Member] \| Minimum [Member] \| Alternative Investments [Member]
Plan Assets
Target allocation percentage	0.00%
Pension Benefits [Member] \| Minimum [Member] \| Company Securities [Member]
Plan Assets
Target allocation percentage	0.00%
Pension Benefits [Member] \| Maximum [Member] \| Equity Securities [Member]
Plan Assets
Target allocation percentage	59.00%
Pension Benefits [Member] \| Maximum [Member] \| Fixed Income Securities [Member]
Plan Assets
Target allocation percentage	57.00%
Pension Benefits [Member] \| Maximum [Member] \| Cash [Member]
Plan Assets
Target allocation percentage	5.00%
Pension Benefits [Member] \| Maximum [Member] \| Alternative Investments [Member]
Plan Assets
Target allocation percentage	2.00%
Pension Benefits [Member] \| Maximum [Member] \| Company Securities [Member]
Plan Assets
Target allocation percentage	10.00%
Pension Benefits [Member] \| U.S.
Pension Plans and OPEB
Vesting period	3 years
OPEB [Member]
Pension Plans and OPEB
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ (17)	(14)	(5)
Components of Accumulated Other Comprehensive Income/Loss
Accumulated benefit obligation whose accumulated benefit obligations exceeded the fair value of plan assets	293	373
Accumulated benefit obligation whose accumulated benefit obligations exceeded the fair value of plan assets, fair value of plan assets	70	84
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	7.26%
Ultimate health care cost trend rate	4.54%
OPEB [Member] \| Minimum [Member] \| Equity Securities [Member]
Plan Assets
Target allocation percentage	42.00%
OPEB [Member] \| Minimum [Member] \| Fixed Income Securities [Member]
Plan Assets
Target allocation percentage	25.00%
OPEB [Member] \| Minimum [Member] \| Cash [Member]
Plan Assets
Target allocation percentage	0.00%
OPEB [Member] \| Maximum [Member] \| Equity Securities [Member]
Plan Assets
Target allocation percentage	67.00%
OPEB [Member] \| Maximum [Member] \| Fixed Income Securities [Member]
Plan Assets
Target allocation percentage	51.00%
OPEB [Member] \| Maximum [Member] \| Cash [Member]
Plan Assets
Target allocation percentage	20.00%
OPEB [Member] \| U.S.
Other Postretirement Benefit Plans
Medicare participation, age	65
Savings plan - defined contribution plan [Member]
Savings Plan
Percentage of eligible compensation contributed	5.00%
Plan cost	$ 48	$ 47	$ 47