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Securities - Schedule of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | $ 134,063 | $ 2,735,499
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (573) | (16,861)
Available-for-sale debt securities, 12 Months or More, Fair Value | 4,245,316 | 4,413,878
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (502,670) | (657,376)
Available-for-sale debt securities fair value, Total | 4,379,379 | 7,149,377
Available-for-sale debt securities, Gross Unrealized Loss, Total | (503,243) | (674,237)
U.S. Treasury securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 596,197 | 638,265
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (20,002) | (38,035)
Available-for-sale debt securities fair value, Total | 596,197 | 638,265
Available-for-sale debt securities, Gross Unrealized Loss, Total | (20,002) | (38,035)
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 256,386 | 262,587
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (31,982) | (45,633)
Available-for-sale debt securities fair value, Total | 256,386 | 262,587
Available-for-sale debt securities, Gross Unrealized Loss, Total | (31,982) | (45,633)
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 2,741
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | (30)
Available-for-sale debt securities, 12 Months or More, Fair Value | 319,280 | 377,756
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (31,039) | (47,177)
Available-for-sale debt securities fair value, Total | 319,280 | 380,497
Available-for-sale debt securities, Gross Unrealized Loss, Total | (31,039) | (47,207)
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 122,698 | 2,719,228
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (503) | (16,404)
Available-for-sale debt securities, 12 Months or More, Fair Value | 1,631,531 | 1,528,252
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (189,697) | (232,382)
Available-for-sale debt securities fair value, Total | 1,754,229 | 4,247,480
Available-for-sale debt securities, Gross Unrealized Loss, Total | (190,200) | (248,786)
Municipal securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 1,949 | 2,763
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (43) | (95)
Available-for-sale debt securities, 12 Months or More, Fair Value | 240,342 | 245,360
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (36,811) | (37,091)
Available-for-sale debt securities fair value, Total | 242,291 | 248,123
Available-for-sale debt securities, Gross Unrealized Loss, Total | (36,854) | (37,186)
Non-agency commercial mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 10,767
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | (332)
Available-for-sale debt securities, 12 Months or More, Fair Value | 196,038 | 235,668
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (23,706) | (35,435)
Available-for-sale debt securities fair value, Total | 196,038 | 246,435
Available-for-sale debt securities, Gross Unrealized Loss, Total | (23,706) | (35,767)
Non-agency residential mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 403,678 | 433,608
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (63,148) | (80,919)
Available-for-sale debt securities fair value, Total | 403,678 | 433,608
Available-for-sale debt securities, Gross Unrealized Loss, Total | (63,148) | (80,919)
Corporate debt securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 2,389 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (11) | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 479,481 | 526,166
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (96,019) | (127,334)
Available-for-sale debt securities fair value, Total | 481,870 | 526,166
Available-for-sale debt securities, Gross Unrealized Loss, Total | (96,030) | (127,334)
Foreign government bonds |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 7,027 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (16) | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 90,440 | 87,008
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (9,560) | (12,992)
Available-for-sale debt securities fair value, Total | 97,467 | 87,008
Available-for-sale debt securities, Gross Unrealized Loss, Total | (9,576) | (12,992)
Asset-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 31,943 | 34,715
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (706) | (371)
Available-for-sale debt securities fair value, Total | 31,943 | 34,715
Available-for-sale debt securities, Gross Unrealized Loss, Total | $ (706) | (371)
Collateralized loan obligations (“CLOs”) |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value |  | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months |  | 0
Available-for-sale debt securities, 12 Months or More, Fair Value |  | 44,493
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More |  | (7)
Available-for-sale debt securities fair value, Total |  | 44,493
Available-for-sale debt securities, Gross Unrealized Loss, Total |  | $ (7)

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-7 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-5 + Details
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