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Securities - Schedule of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
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Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | $ 605,736 | $ 125,924
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (665) | (721)
Available-for-sale debt securities, 12 Months or More, Fair Value | 4,651,745 | 5,532,528
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (570,395) | (728,216)
Available-for-sale debt securities fair value, Total | 5,257,481 | 5,658,452
Available-for-sale debt securities, Gross Unrealized Loss, Total | (571,060) | (728,937)
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 | 641,573 | 623,978
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (34,721) | (52,313)
Available-for-sale debt securities fair value, Total | 641,573 | 623,978
Available-for-sale debt securities, Gross Unrealized Loss, Total | (34,721) | (52,313)
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 | 272,448 | 364,446
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (36,829) | (47,640)
Available-for-sale debt securities fair value, Total | 272,448 | 364,446
Available-for-sale debt securities, Gross Unrealized Loss, Total | (36,829) | (47,640)
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 | 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 | 403,937 | 463,572
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (38,184) | (63,276)
Available-for-sale debt securities fair value, Total | 403,937 | 463,572
Available-for-sale debt securities, Gross Unrealized Loss, Total | (38,184) | (63,276)
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 | 605,736 | 9,402
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (665) | (558)
Available-for-sale debt securities, 12 Months or More, Fair Value | 1,588,241 | 1,661,112
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (194,945) | (229,155)
Available-for-sale debt securities fair value, Total | 2,193,977 | 1,670,514
Available-for-sale debt securities, Gross Unrealized Loss, Total | (195,610) | (229,713)
Municipal securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 2,825
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | (15)
Available-for-sale debt securities, 12 Months or More, Fair Value | 255,356 | 254,773
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (31,840) | (36,327)
Available-for-sale debt securities fair value, Total | 255,356 | 257,598
Available-for-sale debt securities, Gross Unrealized Loss, Total | (31,840) | (36,342)
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 | 2,742
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | (4)
Available-for-sale debt securities, 12 Months or More, Fair Value | 309,524 | 364,774
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (32,236) | (42,058)
Available-for-sale debt securities fair value, Total | 309,524 | 367,516
Available-for-sale debt securities, Gross Unrealized Loss, Total | (32,236) | (42,062)
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 | 479,327 | 553,671
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (68,783) | (89,664)
Available-for-sale debt securities fair value, Total | 479,327 | 553,671
Available-for-sale debt securities, Gross Unrealized Loss, Total | (68,783) | (89,664)
Corporate 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 | 531,819 | 502,425
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (121,682) | (151,076)
Available-for-sale debt securities fair value, Total | 531,819 | 502,425
Available-for-sale debt securities, Gross Unrealized Loss, Total | (121,682) | (151,076)
Foreign government bonds |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 110,955
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | (144)
Available-for-sale debt securities, 12 Months or More, Fair Value | 89,291 | 88,616
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (10,709) | (11,384)
Available-for-sale debt securities fair value, Total | 89,291 | 199,571
Available-for-sale debt securities, Gross Unrealized Loss, Total | (10,709) | (11,528)
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 | 35,735 | 42,300
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (460) | (934)
Available-for-sale debt securities fair value, Total | 35,735 | 42,300
Available-for-sale debt securities, Gross Unrealized Loss, Total | (460) | (934)
Collateralized loan obligations (“CLOs”) |  |
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 | 44,494 | 612,861
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (6) | (4,389)
Available-for-sale debt securities fair value, Total | 44,494 | 612,861
Available-for-sale debt securities, Gross Unrealized Loss, Total | $ (6) | $ (4,389)

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- 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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