CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Securities held to maturity, at fair value	$ 650	$ 705
Loans held-for-sale, at fair value	$ 193	$ 258
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	31,686	26,750
Common stock, par value (in dollars per share)	$ 0.625	$ 0.625
Common stock, shares authorized (in shares)	700,000,000	700,000,000
Common stock, shares issued (in shares)	534,587,149	533,576,766