Credit Quality (Summary of Transactions in the ALLL by Portfolio Segment) (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018		Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Losses charged off	$ 450	[1]	$ 381	$ 456
Recoveries of losses previously charged-off	120	[1]	$ 83	$ 94
Other Consumer Loans, Point of Sale
Financing Receivable, Allowance for Credit Losses [Line Items]
Losses charged off	29
Recoveries of losses previously charged-off	$ 29

[1] (a) For the year ended December 31, 2018, the Bancorp recorded $29 in both losses charged-off and recoveries of losses charged-off related to customer defaults on point-of-sale consumer loans for which the Bancorp obtained recoveries under third-party credit enhancements.