Aggregate cash contribution to pension plan.

No definition available.

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- Definition

Cash contribution term to pension plan.

+ References

No definition available.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(7)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

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- Definition

Amount of payment for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

+ Details

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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 (Detail)			1 Months Ended		3 Months Ended
	Apr. 01, 2018 USD ($)	Nov. 01, 2016 USD ($) Installments	Mar. 31, 2018 USD ($)	Apr. 30, 2017 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
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					$ 143,000,000	$ 31,000,000
Cash contribution term to pension plan		30 months
Number of installments \| Installments		3
Minimum required cash contribution to pension plan		$ 50,000,000
Aggregate cash cash contribution to pension plan		$ 150,000,000
Cash payments made for pension and other post-retirement benefits			$ 50,000,000	$ 50,000,000
Pension Benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailments					$ 5,000,000	$ 0
UNITED STATES \| Pension Benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase (decrease) in obligation, pension benefits	$ 136,000,000
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	141,000,000
Curtailments	$ 5,000,000