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Allowance for Credit Losses - Schedule of Activity in the Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2025 | Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | $ 436,603 | $ 427,265
Other adjustments |  | 167 | (207)
Charge-offs | $ (27,076) | (91,866) | (109,346)
Recoveries |  | 19,551 | 14,950
Provision for credit losses - other |  | 95,750 |
Provision for credit losses |  | 95,800 | 85,390
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 15,547
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 3,004
Allowance for credit losses at period end | 460,205 | 460,205 | 436,603
Individually evaluated for impairment | 24,072 | 24,072 | 34,757
Collectively evaluated for impairment | 436,133 | 436,133 | 401,846
Individually evaluated for impairment | 137,209 | 137,209 | 119,325
Collectively evaluated for impairment | 52,816,302 | 52,816,302 | 47,776,917
Loans held-for-investment | 151,590 | 151,590 | 158,795
Commercial |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | 175,837 | 169,604
Other adjustments |  |  | 0
Charge-offs |  | (50,361) | (48,864)
Recoveries |  | 5,080 | 2,853
Provision for credit losses - other |  | 47,989 |
Provision for credit losses |  |  | 47,439
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 2,967
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 1,838
Allowance for credit losses at period end | 178,545 | 178,545 | 175,837
Individually evaluated for impairment | 19,054 | 19,054 | 27,894
Collectively evaluated for impairment | 159,491 | 159,491 | 147,943
Individually evaluated for impairment | 78,059 | 78,059 | 73,490
Collectively evaluated for impairment | 16,966,627 | 16,966,627 | 15,501,061
Loans held-for-investment | 0 | 0 | 0
Commercial Real Estate |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | 222,856 | 223,853
Other adjustments |  | 0 | 0
Charge-offs |  | (11,934) | (22,127)
Recoveries |  | 267 | 323
Provision for credit losses - other |  | 35,744 |
Provision for credit losses |  |  | 9,164
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 10,540
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 1,103
Allowance for credit losses at period end | 246,933 | 246,933 | 222,856
Individually evaluated for impairment | 4,890 | 4,890 | 6,768
Collectively evaluated for impairment | 242,043 | 242,043 | 216,088
Individually evaluated for impairment | 25,147 | 25,147 | 21,042
Collectively evaluated for impairment | 13,915,589 | 13,915,589 | 12,882,902
Loans held-for-investment | 0 | 0 | 0
Home Equity |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | 8,943 | 7,116
Other adjustments |  | 0 | 0
Charge-offs |  | (138) | (74)
Recoveries |  | 378 | 359
Provision for credit losses - other |  | 1,219 |
Provision for credit losses |  |  | 196
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 1,344
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 2
Allowance for credit losses at period end | 10,402 | 10,402 | 8,943
Individually evaluated for impairment | 0 | 0 | 50
Collectively evaluated for impairment | 10,402 | 10,402 | 8,893
Individually evaluated for impairment | 1,221 | 1,221 | 1,117
Collectively evaluated for impairment | 479,304 | 479,304 | 443,911
Loans held-for-investment | 0 | 0 | 0
Residential Real Estate |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | 10,335 | 13,133
Other adjustments |  | 0 | 0
Charge-offs |  | (26) | (175)
Recoveries |  | 140 | 15
Provision for credit losses - other |  | 2,070 |
Provision for credit losses |  |  | (3,337)
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 638
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 61
Allowance for credit losses at period end | 12,519 | 12,519 | 10,335
Individually evaluated for impairment | 120 | 120 | 44
Collectively evaluated for impairment | 12,399 | 12,399 | 10,291
Individually evaluated for impairment | 32,774 | 32,774 | 23,674
Collectively evaluated for impairment | 4,132,868 | 4,132,868 | 3,430,296
Loans held-for-investment | 151,590 | 151,590 | 158,795
Premium Finance Receivable |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | 17,820 | 13,069
Other adjustments |  | 167 | (207)
Charge-offs |  | (28,704) | (37,519)
Recoveries |  | 13,556 | 11,313
Provision for credit losses - other |  | 8,172 |
Provision for credit losses |  |  | 31,164
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 0
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 0
Allowance for credit losses at period end | 11,011 | 11,011 | 17,820
Individually evaluated for impairment |  |  | 0
Collectively evaluated for impairment | 11,011 | 11,011 | 17,820
Individually evaluated for impairment | 0 | 0 | 0
Collectively evaluated for impairment | 17,207,058 | 17,207,058 | 15,419,187
Loans held-for-investment | 0 | 0 | 0
Consumer and other |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Allowance for credit losses at beginning of period |  | 812 | 490
Other adjustments |  | 0 | 0
Charge-offs |  | (703) | (587)
Recoveries |  | 130 | 87
Provision for credit losses - other |  | 556 |
Provision for credit losses |  |  | 764
Provision for credit losses - Day 1 on non-PCD assets acquired during the period |  |  | 58
Initial allowance for credit losses recognized on PCD assets acquired during the period |  |  | 0
Allowance for credit losses at period end | 795 | 795 | 812
Individually evaluated for impairment | 8 | 8 | 1
Collectively evaluated for impairment | 787 | 787 | 811
Individually evaluated for impairment | 8 | 8 | 2
Collectively evaluated for impairment | 114,856 | 114,856 | 99,560
Loans held-for-investment | $ 0 | $ 0 | $ 0

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of financing receivable collectively evaluated for credit loss. Excludes financing receivable individually evaluated for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.5.a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480418/310-10-S99-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11C -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11C + Details
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