Lease Obligations - Lessee - Undiscounted Cash Flows (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Operating Leases
2022	$ 87
2023	80
2024	72
2025	64
2026	55
Thereafter	238
Total undiscounted cash flows	596
Less: Difference between undiscounted cash flows and discounted cash flows	76
Present value of lease liabilities	520	$ 527
Finance Leases
2022	21
2023	18
2024	18
2025	12
2026	7
Thereafter	111
Total undiscounted cash flows	187
Less: Difference between undiscounted cash flows and discounted cash flows	38
Present value of lease liabilities	149	$ 130
Total
2022	108
2023	98
2024	90
2025	76
2026	62
Thereafter	349
Total undiscounted cash flows	783
Less: Difference between undiscounted cash flows and discounted cash flows	114
Present value of lease liabilities	$ 669

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Lease liability payments due year five.

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Lease liability payments due year four.

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Lease liability payments due year three.

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LeaseLiabilityUndiscountedExcessAmount.

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TotalLeaseLiabilities1.

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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=123408670&loc=SL77918701-209980

Reference 2: 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=123391704&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 payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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