Aggregate cash contribution to pension plan.

No definition available.

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- Definition

Cash contribution term to pension plan.

+ References

No definition available.

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- Definition

Defined Benefit Plan, Labor Agreement, Employees Subject To Retirement Benefit Increase

+ References

No definition available.

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- Definition

Labor Agreement, Number Of Employees

+ References

No definition available.

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- Definition

Labor Agreement, Number Of Locations Covered

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No definition available.

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- Definition

Labor Agreement, One Time Signing Bonus

+ References

No definition available.

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- Definition

Labor Agreement Term

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

+ References

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

Amount of increase (decrease) in obligation for pension benefits. Includes, but is not limited to, defined benefit or defined contribution plans. Excludes other postretirement benefits.

+ References

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-Section 45
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- Definition

Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

+ References

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-Name Accounting Standards Codification
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- Definition

Amount of cash outflow for pension and other postretirement benefits. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree.

+ References

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-Section 45
-Paragraph 25
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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Pension and Other Postretirement Benefits - Narrative (Details) $ in Millions				1 Months Ended				3 Months Ended				6 Months Ended
	Jul. 25, 2019 employee	Apr. 13, 2018 employee	Nov. 01, 2016 USD ($)	Jun. 30, 2019 employee location	Apr. 30, 2019 USD ($)	Mar. 31, 2018 USD ($)	Apr. 30, 2017 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment benefit (charges)										$ (9)
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits								$ 23		29		$ 63	$ 172
Restructuring and other charges (benefits)								499		15		511	22
Labor agreement term		5 years		3 years
Number of employees included in Labor Agreement \| employee		1,300		3,400
Labor agreement, number of locations covered \| location				4
Labor agreement, one time signing bonus								9
Employees subject to retirement benefit increase under Labor Agreement \| employee		300
Aggregate cash contribution to pension plan			$ 150
Cash contribution term to pension plan			30 months
Cash payments made for pension and other post-retirement benefits					$ 34	$ 66	$ 50
Other postretirement benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment benefit (charges)								0		0		58	0
Pension Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment benefit (charges)								0		$ (9)		0	$ (14)
Domestic Plan \| Other postretirement benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Decrease in obligation, pension benefits									$ 63
Curtailment benefit (charges)									(58)
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits									5
Domestic Plan \| Pension Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Decrease in obligation, pension benefits											$ 136
Curtailment benefit (charges)											5
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits											$ 141
Pension Settlement Cost
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restructuring and other charges (benefits)								$ 2				$ 4
Elimination Of Health Care Subsidies \| Domestic Plan \| Other postretirement benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Decrease in obligation, pension benefits									$ 12
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Labor agreement term	4 years
Number of employees included in Labor Agreement \| employee	560