Regulatory Capital Requirements (Capital and Risk-Based Capital and Leverage Ratios for the Bancorp and its Significant Subsidiary Banks) (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fifth Third Bancorp
Risk Based Ratios
CET1 capital ratio (to risk-weighted assets)	9.75%	10.24%
Tier I risk-based capital (to risk-weighted assets)	10.99%	11.32%
Total risk-based capital (to risk-weighted assets)	13.84%	14.48%
Tier I leverage (to quarterly average assets)	9.54%	9.72%
Risk Based Capital
CET1 capital (to risk-weighted assets)	$ 13,847	$ 12,534
Tier I risk-based capital (to risk-weighted assets)	15,616	13,864
Total risk-based capital (to risk weighted assets)	19,661	17,723
Tier I leverage (to quarterly average assets)	$ 15,616	$ 13,864
Fifth Third Bancorp \| Well Capitalized
Risk Based Ratios
Tier I risk-based capital (to risk-weighted assets)	6.00%
Total risk-based capital (to risk-weighted assets)	10.00%
Fifth Third Bancorp \| Minimum
Risk Based Ratios
CET1 capital ratio (to risk-weighted assets)	4.50%
Tier I risk-based capital (to risk-weighted assets)	6.00%
Total risk-based capital (to risk-weighted assets)	8.00%
Tier I leverage (to quarterly average assets)	4.00%
Fifth Third Bank, National Association
Risk Based Ratios
CET1 capital ratio (to risk-weighted assets)	11.86%	11.93%
Tier I risk-based capital (to risk-weighted assets)	11.86%	11.93%
Total risk-based capital (to risk-weighted assets)	13.46%	13.57%
Tier I leverage (to quarterly average assets)	10.36%	10.27%
Risk Based Capital
CET1 capital (to risk-weighted assets)	$ 16,704	$ 14,435
Tier I risk-based capital (to risk-weighted assets)	16,704	14,435
Total risk-based capital (to risk weighted assets)	18,968	16,427
Tier I leverage (to quarterly average assets)	$ 16,704	$ 14,435
Fifth Third Bank, National Association \| Well Capitalized
Risk Based Ratios
CET1 capital ratio (to risk-weighted assets)	6.50%
Tier I risk-based capital (to risk-weighted assets)	8.00%
Total risk-based capital (to risk-weighted assets)	10.00%
Tier I leverage (to quarterly average assets)	5.00%
Fifth Third Bank, National Association \| Minimum
Risk Based Ratios
CET1 capital ratio (to risk-weighted assets)	4.50%
Tier I risk-based capital (to risk-weighted assets)	6.00%
Total risk-based capital (to risk-weighted assets)	8.00%
Tier I leverage (to quarterly average assets)	4.00%

The amount of total capital as defined in the regulations.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Risk Based Capital as defined in the regulations.

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