Consolidated Statement of Condition (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Current Assets:
Investment securities held-to-maturity, fair value	$ 42,157	$ 41,351
Loans, allowance for losses	74	67
Premises and equipment, accumulated depreciation	$ 4,367	$ 4,152
Stockholders' Equity:
Preferred stock, no par value (in USD per share)	$ 0	$ 0
Preferred stock, shares authorized (in shares)	3,500,000	3,500,000
Common stock, par value (in USD per share)	$ 1.00	$ 1.00
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued (in shares)	503,879,642	503,879,642
Common stock, shares outstanding (in shares)	357,389,416	379,946,724
Treasury stock, shares (in shares)	146,490,226	123,932,918
Series C Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	5,000	5,000
Preferred stock, shares outstanding (in shares)	5,000	5,000
Series D Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	7,500	7,500
Preferred stock, shares outstanding (in shares)	7,500	7,500
Series E Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	7,500	7,500
Preferred stock, shares outstanding (in shares)	7,500	7,500
Series F Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	7,500	7,500
Preferred stock, shares outstanding (in shares)	7,500	7,500
Series G Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	5,000	5,000
Preferred stock, shares outstanding (in shares)	5,000	5,000
Series H Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	5,000	5,000
Preferred stock, shares outstanding (in shares)	5,000	5,000