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Regulatory Capital - Additional Information (Detail) - USD ($) | Jan. 01, 2019 | Mar. 31, 2020
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Capital conservation buffer risk-weighted assets | 2.50% |
Maximum asset value required to be maintained leverage ratio |  | $ 10,000,000,000
Minimum [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Leverage ratio |  | 8.00%
Maximum [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Leverage ratio |  | 9.00%

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- Definition Maximum Asset Value Required To Be Maintained Leverage Ratio. + References No definition available. + Details
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- Definition Tier one risk based capital to risk weighted assets conservation buffer. + References No definition available. + Details
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- Definition Tier 1 Leverage Capital divided by average assets as defined in the regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117337116&loc=d3e65071-112826 + Details
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