Basis of Presentation - Additional Information (Detail) - USD ($) $ in Millions		9 Months Ended
Jan. 01, 2019	Sep. 30, 2019
Disclosure Basis Of Presentation Details [Line Items]
Operating lease right-of-use asset		$ 589
Operating lease liabilities	$ 502	494
ASU 2016-02
Disclosure Basis Of Presentation Details [Line Items]
Operating lease right-of-use asset	502
ASU 2018-02
Disclosure Basis Of Presentation Details [Line Items]
Other comprehensive income to retained earnings	$ 161	$ (161)

Disclosure basis of presentation details.

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- Definition

Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

+ References

No definition available.

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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