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Regulatory Requirements - Regulatory Capital Amounts And Ratios Compared To Regulatory Requirements (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
CBLR, amount | $ 696,368 |
CBLR, ratio | 12.93% |
CBLR, for capital adequacy purposes amount | $ 457,751 |
CBLR, for capital adequacy purposes ratio | 8.50% |
CBLR, for well capitalized under prompt corrective action provisions amount | $ 457,751 |
CBLR, for well capitalized under prompt corrective action provisions ratio | 8.50% |
Common Equity Tier 1 Capital (to risk-weighted assets), amount |  | $ 698,864
Common Equity Tier 1 Capital (to risk-weighted assets), ratio |  | 12.73%
Common Equity Tier 1 Capital (to risk-weighted assets), for capital adequacy purposes amount |  | $ 439,219
Common Equity Tier 1 Capital (to risk-weighted assets), for capital adequacy purposes ratio | 4.50% | 8.00%
Common Equity Tier 1 Capital (to risk-weighted assets), for well capitalized under prompt corrective action provisions amount |  | $ 439,219
Common Equity Tier 1 Capital (to risk-weighted assets), for well capitalized under prompt corrective action provisions ratio | 6.50% | 8.00%
Subsidiaries |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
CBLR, amount | $ 659,522 |
CBLR, ratio | 12.24% |
CBLR, for capital adequacy purposes amount | $ 457,872 |
CBLR, for capital adequacy purposes ratio | 8.50% |
CBLR, for well capitalized under prompt corrective action provisions amount | $ 457,872 |
CBLR, for well capitalized under prompt corrective action provisions ratio | 8.50% |
Common Equity Tier 1 Capital (to risk-weighted assets), amount |  | $ 656,324
Common Equity Tier 1 Capital (to risk-weighted assets), ratio |  | 11.96%
Common Equity Tier 1 Capital (to risk-weighted assets), for capital adequacy purposes amount |  | $ 439,124
Common Equity Tier 1 Capital (to risk-weighted assets), for capital adequacy purposes ratio |  | 8.00%
Common Equity Tier 1 Capital (to risk-weighted assets), for well capitalized under prompt corrective action provisions amount |  | $ 439,124
Common Equity Tier 1 Capital (to risk-weighted assets), for well capitalized under prompt corrective action provisions ratio |  | 8.00%

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