Leases - Schedule of Annual Maturities of Lease Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Jan. 01, 2019
Leases [Abstract]
Operating Leases, July 1, 2019 to December 31, 2019	$ 93
Operating Leases, 2020	111
Operating Leases, 2021	84
Operating Leases, 2022	70
Operating Leases, 2023	52
Operating Leases, 2024	35
Operating Leases, Thereafter	195
Operating Leases, Total lease payments	640
Operating Leases, Less imputed interest	(111)
Operating Leases, Total	529	$ 500
Finance Leases, July 1, 2019 to December 31, 2019	46
Finance Leases, 2020	48
Finance Leases, 2021	33
Finance Leases, 2022	18
Finance Leases, 2023	11
Finance Leases, 2024	4
Finance Leases, Thereafter	9
Finance Leases, Total lease payments	169
Finance Leases, Less imputed interest	(18)
Finance Leases, Total	$ 151

Finance lease liability payments due after year six.

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Finance lease liability payments due year six.

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Lessee operating lease liability payments due after year six.

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Lessee operating lease liability payments due year five.

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Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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-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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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in remainder of fiscal year following latest fiscal year ended.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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-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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