Summary of Significant Accounting Policies - Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Renewal term	20 years
Lease, option to terminate	32 days
Operating lease, liability, extensible enumeration	Other liabilities and accrued expenses	Other liabilities and accrued expenses
Operating lease, right-of-use asset, extensible enumeration	Other assets, net	Other assets, net
Lease liability	$ 465	$ 511
Right of use asset	314	393
Lease, cost	162	166
Variable lease, cost	$ 30	$ 30
Weighted average remaining lease term (years)	5 years	5 years
Weighted average discount rate	3.09%	3.10%
2022	$ 95
2023	125
2024	101
2025	79
2026	48
Thereafter	56
Total lease payments	504
Less: interest	(39)
Present value of lease liabilities	$ 465	$ 511
Minimum
Lessee, Lease, Description [Line Items]
Lease, term of contract	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lease, term of contract	9 years