Capital and Risk-Based Capital and Leverage Ratios for the Bancorp and its Significant Subsidiary Banks (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fifth Third Bancorp (Consolidated)
Risk Based Ratios
Tier I risk-based capital (to risk-weighted assets)	10.83%	10.43%
Total risk-based capital (to risk-weighted assets)	14.33%	14.17%
Tier I leverage (to average assets)	9.66%	9.73%
Risk Based Capital
Tier I risk-based capital (to risk-weighted assets)	$ 12,764	$ 12,094
Total risk-based capital (to risk weighted assets)	16,895	16,431
Tier I leverage (to average assets)	12,764	12,094
Fifth Third Bank
Risk Based Ratios
Tier I risk-based capital (to risk-weighted assets)	11.85%	11.59%
Total risk-based capital (to risk-weighted assets)	13.10%	12.94%
Tier I leverage (to average assets)	10.58%	10.83%
Risk Based Capital
Tier I risk-based capital (to risk-weighted assets)	13,760	13,245
Total risk-based capital (to risk weighted assets)	15,213	14,785
Tier I leverage (to average assets)	$ 13,760	$ 13,245

The amount of total capital as defined in the regulations.

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