Capital Ratios (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Common Equity Tier One Capital	$ 17,258	$ 17,141
Tier 1 capital	19,306	19,622
Total capital	$ 22,517	$ 23,028
Common Equity Tier One Capital Ratio	9.21%	9.74%
Tier 1 capital	10.30%	11.15%
Total capital	12.02%	13.09%
Tier One Leverage Capital to Average Assets	9.26%	9.80%
Sun Trust Bank [Member]
Common Equity Tier One Capital	$ 20,137	$ 19,474
Tier 1 capital	20,160	19,496
Total capital	$ 22,564	$ 22,132
Common Equity Tier One Capital Ratio	11.01%	11.29%
Tier 1 capital	11.02%	11.31%
Total capital	12.33%	12.83%
Tier One Leverage Capital to Average Assets	9.95%	9.97%
Minimum [Member]
Common Equity Tier One Capital Ratio	4.50%
Tier 1 capital	6.00%
Total capital	8.00%
Tier One Leverage Capital to Average Assets	4.00%
Capital Required for Capital Adequacy to Risk Weighted Assets	2.50%

The amount of total capital as defined in the regulations.

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