Aggregate cash contribution to pension plan.

No definition available.

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Period Type:	duration

- Definition

Cash contribution term to pension plan.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Labor Agreement, Duration

+ References

No definition available.

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- Definition

Labor Agreement, Number Of Employees

+ References

No definition available.

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- Definition

Minimum required cash contribution to pension plan.

+ References

No definition available.

+ Details

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- Definition

Number of installment made for cash contribution to pension plan.

+ References

No definition available.

+ Details

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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

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ 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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-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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Period Type:	duration

- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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- 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.

+ Details

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Pension and Other Postretirement Benefits - Narrative (Details) $ in Millions			1 Months Ended		3 Months Ended					9 Months Ended		12 Months Ended
	Apr. 13, 2018 employee	Nov. 01, 2016 USD ($) Installments	Mar. 31, 2018 USD ($)	Apr. 30, 2017 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits						$ 37			$ 31	$ 209	$ 110
Curtailment benefit (charges)							$ (9)
Cash contribution term to pension plan		30 months
Number of installments \| Installments		3
Minimum required cash contribution to pension plan		$ 50
Aggregate cash cash contribution to pension plan		$ 150
Cash payments made for pension and other post-retirement benefits			$ 50	$ 50				$ 16		116
Labor agreement, duration	5 years
Labor agreement, number of employees \| employee	1,300
Defined benefit plan, labor agreement, employees subject to retirement benefit increase \| employee	300
Scenario, Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash payments made for pension and other post-retirement benefits												$ 34
Pension benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment benefit (charges)						0			0	(14)	0
Charge recorded						9			23	37	67
Other postretirement benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Decrease in obligation, pension benefits						32
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits						4
Curtailment benefit (charges)						28			0	28	0
Charge recorded						2			$ 2	$ 6	$ 6
UNITED STATES \| Pension benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Decrease in obligation, pension benefits								136
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits								141
Curtailment benefit (charges)								$ (5)
Charge recorded						$ 4
UNITED STATES \| Pension benefits \| Scenario, Forecast \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Charge recorded					$ 70
UNITED STATES \| Pension benefits \| Scenario, Forecast \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Charge recorded					$ 85