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Regulatory Capital Requirements (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Capital Conservation Buffer | 5.98% |
Common Equity Tier One Capital | $ 1,885,860 | $ 1,710,981
Common Equity Tier 1 Capital to Risk Weighted Assets | 12.87% | 13.01%
Common Equity Tier One Capital Required for Capital Adequacy | $ 659,248 | $ 591,585
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 | $ 1,025,498 | $ 920,244
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 | $ 1,885,860 | $ 1,710,981
Tier 1 Capital (to risk-weighted assets), Ratio | 0.1287 | 0.1301
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 878,998 | $ 788,780
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 | $ 1,245,247 | $ 1,117,439
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 | $ 2,048,700 | $ 1,868,192
Total Capital (to risk-weighted assets), Ratio | 0.1398 | 0.1421
Total Capital For Capital Adequacy Purposes, Amount | $ 1,171,997 | $ 1,051,707
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 | $ 1,538,246 | $ 1,380,366
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 | $ 1,885,860 | $ 1,710,981
Tier 1 Capital (to average assets), Ratio | 0.0934 | 0.0855
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 807,791 | $ 800,615
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 | 5.97% |
Common Equity Tier One Capital | $ 1,892,755 | $ 1,716,186
Common Equity Tier 1 Capital to Risk Weighted Assets | 12.93% | 13.06%
Common Equity Tier One Capital Required for Capital Adequacy | $ 658,773 | $ 591,154
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 | $ 1,024,758 | $ 919,754
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 | $ 951,561 | $ 853,890
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 | $ 1,892,755 | $ 1,716,186
Tier 1 Capital (to risk-weighted assets), Ratio | 0.1293 | 0.1306
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 878,364 | $ 788,206
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 | $ 1,244,349 | $ 1,116,625
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 | $ 1,171,152 | $ 1,050,941
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 | $ 2,045,595 | $ 1,863,397
Total Capital (to risk-weighted assets), Ratio | 0.1397 | 0.1418
Total Capital For Capital Adequacy Purposes, Amount | $ 1,171,152 | $ 1,050,941
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 | $ 1,537,137 | $ 1,379,360
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 | $ 1,463,940 | $ 1,313,677
Total Capital (to risk-weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provision | 0.1000 | 0.1000
Tier 1 Capital, Actual Amount | $ 1,892,755 | $ 1,716,186
Tier 1 Capital (to average assets), Ratio | 0.0947 | 0.0860
Tier 1 Capital For Capital Adequacy Purposes, Amount | $ 799,485 | $ 798,206
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 | $ 999,356 | $ 997,757
Tier 1 Capital (to average assets) To Be Well Capitalized Under Prompt Corrective Provision, Ratio | 0.0500 | 0.0500

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