Occupancy Expense and Information Systems and Communications Expense - Summary of Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Operating Leases
2022	$ 158
2023	140
2024	117
2025	98
2026	74
Thereafter	162
Total future minimum lease payments	749
Less imputed interest	(60)
Total	689
Finance Leases
2022	71
2023	60
2024	29
2025	10
2026	0
Thereafter	0
Total future minimum lease payments	170
Less imputed interest	(6)
Total	164	$ 103
2022	229
2023	200
2024	146
2025	108
2026	74
Thereafter	162
Total future minimum lease payments	919
Less imputed interest	(66)
Total	$ 853

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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