Investment Securities (Gains and Losses Recognized in Income from Securities) (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Securities
Available-for-sale debt and other securities, realized gains		$ 72	$ 85	$ 72
Available-for-sale debt and other securities, realized losses		82	36	49
OTTI		0	(54)	(15)
Net realized gains (losses) on available-for-sale debt and other securities		(10)	(5)	8
Total trading debt securities gains (losses)		(15)	2	0
Total equity securities gains (losses)	[1]	(44)	7	2
Total available for sale debt and other, trading debt and equity securities gains (losses) recognized in income	[2]	$ (69)	$ 4	$ 10

[1] Includes $ 45 of net unrealized losses for the year ended December 31, 2018 and net unrealized gains of $ 5 and $ 3 for the years ended December 31, 2017 and 2016 , respectively.

[2] Excludes an insignificant amount of securities gains (losses) included in corporate banking revenue and wealth and asset management revenue in the Consolidated Statements of Income related to securities held by FTS to facilitate the timely execution of customer transactions.