Regulation and Capital Adequacy - Risk-based Capital and Leverage Requirements (Detail) |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] | ||
| Tier 1 leverage ratio | 0.040 | 0.040 |
| SLR | 5.00% | 5.00% |
| Standardized Capital Rules [Member] | ||
| Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] | ||
| CET1 capital ratio | 13.60% | 9.50% |
| Tier 1 capital ratio | 0.151 | 0.110 |
| Total capital ratio | 0.171 | 0.130 |
| Advanced Capital Rules [Member] | ||
| Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] | ||
| CET1 capital ratio | 9.50% | 9.50% |
| Tier 1 capital ratio | 0.110 | 0.110 |
| Total capital ratio | 0.130 | 0.130 |