CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
ASSETS:
Securities held-to-maturity, fair value	$ 2,790	$ 3,357
STOCKHOLDERS’ EQUITY:
Preferred stock, par value (in dollars per share)	$ 25.00	$ 25.00
Preferred stock, authorized (in shares)	100,000,000	100,000,000
Preferred stock, issued (in shares)	2,050,000	2,000,000
Preferred stock, outstanding (in shares)	2,050,000	2,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, issued (in shares)	570,994,369	569,876,133
Common stock, outstanding (in shares)	426,083,143	427,209,831
Treasury stock (in shares)	144,911,226	142,666,302
Available-for-sale Securities
ASSETS:
Securities, pledged to creditors	$ 568	$ 549
Held-to-maturity Securities
ASSETS:
Securities, pledged to creditors	124	144
Securities held-to-maturity, fair value	$ 2,790	$ 3,357