Leases - Maturities of Operating and Finance Lease Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Finance Leases
2021	$ 100
2022	98
2023	96
2024	95
2025	95
Thereafter	1,328
Total lease payments	1,812
Less: imputed interest	(729)
Total finance lease liabilities	1,083	$ 808
Operating Leases
2021	2,688
2022	2,583
2023	2,496
2024	2,269
2025	2,089
Thereafter	15,017
Total lease payments	27,142
Less: imputed interest	(6,747)
Total operating lease liabilities	20,395	$ 20,522
Total
2021	2,788
2022	2,681
2023	2,592
2024	2,364
2025	2,184
Thereafter	16,345
Total lease payments	28,954
Less: imputed interest	(7,476)
Total lease liabilities	21,478
Future noncancelable subleases, future minimum payments	306
Leases, amount due in excess of remaining estimated economic life	$ 2,300

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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