CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
ASSETS:
Securities held-to-maturity, fair value	$ 3,219	$ 3,242
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)	1,600,000	1,600,000
Preferred stock, outstanding (in shares)	1,600,000	1,600,000
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)	569,252,835	568,238,730
Common stock, outstanding (in shares)	426,586,533	433,121,083
Treasury stock (in shares)	142,666,302	135,117,647
Available-for-sale Securities
ASSETS:
Securities, pledged to creditors	$ 491	$ 359
Held-to-maturity Securities
ASSETS:
Securities, pledged to creditors	204	249
Securities held-to-maturity, fair value	$ 3,219	$ 3,242

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