Pension and Other Postretirement Benefits - Schedule of Amounts Expected to be Recognized in Net Periodic Benefit Cost (Detail) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Pension benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss recognition	$ 176
Prior service cost (benefit) recognition	$ 0
Other postretirement benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss recognition		$ 8
Prior service cost (benefit) recognition		$ (7)

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.

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (s)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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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.

+ References

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