Lease Obligations - Schedule of Future Minimum Lease Payments for Operating and Finance Lease Obligations (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Operating leases
2020	$ 102
2021	89
2022	77
2023	61
2024	54
After 2024	287
Total lease payments	670
Less: Interest	(268)
Present value of lease liabilities	402
Finance leases
2020	8
2021	8
2022	8
2023	8
2024	8
After 2024	24
Total lease payments	64
Less: Interest	(17)
Present value of lease liabilities	47
Operating and financing leases
2020	110
2021	97
2022	85
2023	69
2024	62
After 2024	311
Total lease payments	734
Less: Interest	(285)
Present value of lease liabilities	$ 449	$ 74

Operating and finance lease liabilities payments due.

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Operating and finance lease liability payments due next twelve months.

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Operating and finance lease liability payments due year five.

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Operating and finance lease liability payments due year four.

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Operating and finance lease liability payments due year three.

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Operating and finance lease liability undiscounted excess amount.

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

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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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