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v3.25.1

Investments - Amortized Cost and Fair Value of Securities Available for Sale (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,747,064 | $ 2,042,473
Allowance for credit losses | 0 | 0
Gross Unrealized Gains | 9,855 | 8,838
Gross Unrealized Losses | (99,942) | (118,085)
Estimated Fair Value | 1,656,977 | 1,933,226
Mortgage-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 544,422 | 516,358
Allowance for credit losses | 0 | 0
Gross Unrealized Gains | 621 | 205
Gross Unrealized Losses | (64,620) | (73,235)
Estimated Fair Value | 480,423 | 443,328
Utah Housing Corporation bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,659 | 2,849
Allowance for credit losses | 0 | 0
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (409) | (490)
Estimated Fair Value | 2,250 | 2,359
U.S. government-sponsored enterprises and Treasuries |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 648,413 | 948,009
Allowance for credit losses | 0 | 0
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (24,058) | (32,265)
Estimated Fair Value | 624,355 | 915,744
Other securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 551,570 | 575,257
Allowance for credit losses | 0 | 0
Gross Unrealized Gains | 9,234 | 8,633
Gross Unrealized Losses | (10,855) | (12,095)
Estimated Fair Value | $ 549,949 | $ 571,795

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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