Derivatives (Net Gains (Losses) Relating to Derivative Instruments Designated as Cash Flow Hedges) (Detail) - Cash Flow Hedging - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	[1]	Dec. 31, 2016	[1]
Derivative Instruments, Gain (Loss)
Amount of pretax net (losses) gains recognized in OCI	$ 214	$ (11)		$ 30
Interest Income (Expense) Net
Derivative Instruments, Gain (Loss)
Amount of pretax net gains (losses) reclassified from OCI into net income	$ (2)	$ 19		$ 48

[1] For both the years ended December 31, 2017 and 2016 , the amount of pre - tax net losses recognized in OCI represented the effective portion of the cumulative gains or losses on cash flow hedges and ineffectiveness was reported within noninterest income. Upon the adoption of ASU 2017-12, the Bancorp recorded a cumulative effect adjustment to retained earnings effective January 1, 2018 related to the elimination of the separate measurement of ineffectiveness. Refer to Note 1 for additional information.