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Regulatory Capital 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] |  |
Capital Conservation Buffer | 6.21% |
Common Equity Tier One Capital | $ 1,710,981 | $ 1,390,958
Common Equity Tier 1 Capital to Risk Weighted Assets | 13.01% | 12.88%
Common Equity Tier One Capital Required for Capital Adequacy | $ 591,585 | $ 486,080
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy - minimum required plus fully phased in capital conservation buffer | $ 920,244 | $ 756,125
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets plus capital conservation buffer fully phased-in | 7.00% | 7.00%
Tier 1 Capital, Actual Amount | $ 1,710,981 | $ 1,390,958
Tier 1 Capital (to risk-weighted assets), Ratio | 0.1301 | 0.1288
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 788,780 | $ 648,107
Tier 1 Capital (to risk-weighted assets) For Capital Adequacy Purposes, Ratio | 0.0600 | 0.0600
Tier One Risk Based Capital Required for Capital Adequacy plus capital conservation buffer fully phased-in | $ 1,117,439 | $ 918,152
Tier One Based Capital Required for Capital Adequacy to Risk Weighted Assets plus capital conservation buffer fully phased-in | 8.50% | 8.50%
Total Capital, Actual Amount | $ 1,868,192 | $ 1,561,020
Total Capital (to risk-weighted assets), Ratio | 0.1421 | 0.1445
Total Capital For Capital Adequacy Purposes, Amount | $ 1,051,707 | $ 864,143
Total Capital (to risk-weighted assets), For Capital Adequacy Purposes, Ratio | 0.0800 | 0.0800
Capital Required for Capital Adequacy plus capital conservation buffer fully phased-in | $ 1,380,366 | $ 1,134,187
Capital Required for Capital Adequacy to Risk Weighted Assets plus capital conservation buffer fully phased-in | 10.50% | 10.50%
Tier 1 Capital, Actual Amount | $ 1,710,981 | $ 1,390,958
Tier 1 Capital (to average assets), Ratio | 0.0855 | 0.0886
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 800,615 | $ 628,112
Tier 1 Capital (to average assets) For Capital Adequacy Purposes, Ratio | 0.0400 | 0.0400
Banking Subsidiaries |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Capital Conservation Buffer | 6.18% |
Common Equity Tier One Capital | $ 1,716,186 | $ 1,411,834
Common Equity Tier 1 Capital to Risk Weighted Assets | 13.06% | 13.08%
Common Equity Tier One Capital Required for Capital Adequacy | $ 591,154 | $ 485,775
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy - minimum required plus fully phased in capital conservation buffer | $ 919,754 | $ 755,651
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets plus capital conservation buffer fully phased-in | 7.00% | 7.00%
Common Equity Tier One Risk Based Capital Required to be Well Capitalized | $ 853,890 | $ 701,676
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 6.50% | 6.50%
Tier 1 Capital, Actual Amount | $ 1,716,186 | $ 1,411,834
Tier 1 Capital (to risk-weighted assets), Ratio | 0.1306 | 0.1308
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 788,206 | $ 647,700
Tier 1 Capital (to risk-weighted assets) For Capital Adequacy Purposes, Ratio | 0.0600 | 0.0600
Tier One Risk Based Capital Required for Capital Adequacy plus capital conservation buffer fully phased-in | $ 1,116,625 | $ 917,576
Tier One Based Capital Required for Capital Adequacy to Risk Weighted Assets plus capital conservation buffer fully phased-in | 8.50% | 8.50%
Tier 1 Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Amount | $ 1,050,941 | $ 863,601
Tier 1 Capital (to risk-weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provision, Ratio | 0.0800 | 0.0800
Total Capital, Actual Amount | $ 1,863,397 | $ 1,546,804
Total Capital (to risk-weighted assets), Ratio | 0.1418 | 0.1433
Total Capital For Capital Adequacy Purposes, Amount | $ 1,050,941 | $ 863,601
Total Capital (to risk-weighted assets), For Capital Adequacy Purposes, Ratio | 0.0800 | 0.0800
Capital Required for Capital Adequacy plus capital conservation buffer fully phased-in | $ 1,379,360 | $ 1,133,476
Capital Required for Capital Adequacy to Risk Weighted Assets plus capital conservation buffer fully phased-in | 10.50% | 10.50%
Total Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Amount | $ 1,313,677 | $ 1,079,501
Total Capital (to risk-weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provision | 0.1000 | 0.1000
Tier 1 Capital, Actual Amount | $ 1,716,186 | $ 1,411,834
Tier 1 Capital (to average assets), Ratio | 0.0860 | 0.0908
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 798,206 | $ 622,171
Tier 1 Capital (to average assets) For Capital Adequacy Purposes, Ratio | 0.0400 | 0.0400
Tier 1 Capital To Be Well Capitalized Under Prompt Corrective Provision, Amount | $ 997,757 | $ 777,714
Tier 1 Capital (to average assets) To Be Well Capitalized Under Prompt Corrective Provision, Ratio | 0.0500 | 0.0500

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