v3.8.0.1

Regulatory Matters - Additional Information (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Jan. 01, 2016
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Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items] |  |
CET1 capital ratio, for capital adequacy purposes ratio | 4.50% |
CET1 leverage ratio, to be well-capitalized under prompt corrective action provisions ratio | 6.50% |
Capital buffer against risk weighted assets percentage |  | 0.625%
Capital buffer against risk weighted assets increasing percentage annually | 0.625% |
Capital buffer against risk weighted assets cumulative | 2.50% |
FFB |  |
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items] |  |
CET1 capital ratio, to be well-capitalized amount | $ 200 |
Tier 1 leverage ratio, to be well-capitalized amount | 182 |
Tier 1 risk-based capital ratio, to be well-capitalized amount | 155 |
Excess total risk-based capital ratio, to be well-capitalized amount | $ 113 |

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- Definition Capital buffer against risk weighted assets cumulative percentage. + References No definition available. + Details
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- Definition Capital buffer against risk weighted assets increasing percentage. + References No definition available. + Details
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- Definition Excess tier one leverage capital required to be well capitalized. + References No definition available. + Details
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- Details
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