Regulatory Capital Requirements and Capital Ratios (Details) $ in Millions	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Risk Based Ratios
Banking regulation, capital conservation buffer, capital conserved, minimum	0.025
Fifth Third Bancorp
Risk Based Ratios
CET1 capital (as a percent)	0.0928	0.0954
Tier I risk-based capital (as a percent)	0.1053	0.1091
Total risk-based capital (as a percent)	0.1279	0.1342
Tier I leverage (as a percent)	0.0856	0.0827
Risk Based Capital
CET1 capital	$ 15,670	$ 14,781
Tier I risk-based capital	17,786	16,897
Total risk-based capital	21,606	20,789
Tier I leverage	$ 17,786	$ 16,897
Fifth Third Bancorp | Well-Capitalized
Risk Based Ratios
Tier I risk-based capital (as a percent)	0.0600
Total risk-based capital (as a percent)	0.1000
Fifth Third Bancorp | Minimum
Risk Based Ratios
CET1 capital (as a percent)	0.0450
Tier I risk-based capital (as a percent)	0.0600
Total risk-based capital (as a percent)	0.0800
Tier I leverage (as a percent)	0.0400
Fifth Third Bank, National Association
Risk Based Ratios
CET1 capital (as a percent)	0.1131	0.1090
Tier I risk-based capital (as a percent)	0.1131	0.1090
Total risk-based capital (as a percent)	0.1281	0.1233
Tier I leverage (as a percent)	0.0923	0.0829
Risk Based Capital
CET1 capital	$ 18,952	$ 16,723
Tier I risk-based capital	18,952	16,723
Total risk-based capital	21,463	18,917
Tier I leverage	$ 18,952	$ 16,723
Fifth Third Bank, National Association | Well-Capitalized
Risk Based Ratios
CET1 capital (as a percent)	0.0650
Tier I risk-based capital (as a percent)	0.0800
Total risk-based capital (as a percent)	0.1000
Tier I leverage (as a percent)	0.0500
Fifth Third Bank, National Association | Minimum
Risk Based Ratios
CET1 capital (as a percent)	0.0450
Tier I risk-based capital (as a percent)	0.0600
Total risk-based capital (as a percent)	0.0800
Tier I leverage (as a percent)	0.0400