VIE (Assets and Liabilities Related to Non-consolidated VIEs and Maximum Exposure to Losses) (Detail) - Variable Interest Entity, Not Primary Beneficiary - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Fifth Third Community Development Corporation Investments
Variable Interest Entity
Total Assets	$ 1,424	$ 1,421
Total Liabilities	362	357
Maximum Exposure	1,424	1,421
Private Equity Investments
Variable Interest Entity
Total Assets	121	176
Total Liabilities	0	0
Maximum Exposure	178	232
Loans Provided to VIEs
Variable Interest Entity
Total Assets	1,744	1,735
Total Liabilities	0	0
Maximum Exposure	$ 2,762	$ 2,672