Mortgage Servicing Rights - Changes in the Fair Value of Residential First Mortgage MSRs (Details) - Residential First Mortgage $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)
Servicing Assets at Fair Value [Line Items]
Balance at beginning of period	$ 1,012
Additions from loans sold with servicing retained	19
Decreases in MSR fair value due to pay-offs, pay-downs, run-off, model changes, and other	$ (8)	[1]
Servicing Asset, Fair Value, Change in Fair Value, Valuation Input, Statement of Income or Comprehensive Income [Extensible Enumeration]	Net Return On Mortgage Servicing Rights
Changes in estimates of fair value due to interest rate risk	$ 10	[1],[2]
Fair value of MSRs at end of period	$ 1,033

[1] Changes in fair value are included within net return on mortgage servicing rights on the Consolidated Statements of Income and Comprehensive Income.

[2] Represents estimated MSR value change resulting primarily from market-driven changes which we manage through the use of derivatives.