Investments (Tables)

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

Schedule of Amortized Cost and Fair Value of Securities Available-for-Sale

The amortized cost and fair value of securities available for sale are as follows:


As of September 30, 2025 (dollars in thousands)	Amortized Cost		Allowance for credit losses(1)		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Available-for-sale:
Mortgage-backed securities	$	550,645	$	—	$	1,796	$	(56,821)	$	495,620
Utah Housing Corporation bonds	2,490		—		—		(350)		2,140
U.S. government-sponsored enterprises and Treasuries	648,861		—		—		(14,283)		634,578
Other securities	639,147		—		12,785		(8,486)		643,446
Total	$	1,841,143	$	—	$	14,581	$	(79,940)	$	1,775,784

As of December 31, 2024 (dollars in thousands)	Amortized Cost		Allowance for credit losses(1)		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Available-for-sale:
Mortgage-backed securities	$	516,358	$	—	$	205	$	(73,235)	$	443,328
Utah Housing Corporation bonds	2,849		—		—		(490)		2,359
U.S. government-sponsored enterprises and Treasuries	948,009		—		—		(32,265)		915,744
Other securities	575,257		—		8,633		(12,095)		571,795
Total	$	2,042,473	$	—	$	8,838	$	(118,085)	$	1,933,226

(1) Represents the amount of impairment that has resulted from credit-related factors and that was recognized in the consolidated balance sheets (as a credit loss expense on available-for-sale securities). The amount excludes unrealized losses related to non-credit factors.

Schedule of Available-for-Sale Securities, Continuous Unrealized Loss Position, Fair Value

The following table summarizes the amount of gross unrealized losses for our available-for-sale securities and the estimated fair value for securities having gross unrealized loss positions, categorized by length of time the securities have been in an unrealized loss position:


(Dollars in thousands)	Less than 12 months				12 months or more				Total
	Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value
As of September 30, 2025:
Mortgage-backed securities	$	(54)	$	24,443	$	(56,767)	$	296,952	$	(56,821)	$	321,395
Utah Housing Corporation bonds	—		—		(350)		2,140		(350)		2,140
U.S. government-sponsored enterprises and Treasuries	—		—		(14,283)		634,578		(14,283)		634,578
Other securities	(92)		21,628		(8,394)		128,021		(8,486)		149,649
Total	$	(146)	$	46,071	$	(79,794)	$	1,061,691	$	(79,940)	$	1,107,762

As of December 31, 2024:
Mortgage-backed securities	$	(2,723)	$	137,585	$	(70,512)	$	290,257	$	(73,235)	$	427,842
Utah Housing Corporation bonds	—		—		(490)		2,359		(490)		2,359
U.S. government-sponsored enterprises and Treasuries	—		—		(32,265)		915,744		(32,265)		915,744
Other securities	(74)		11,579		(12,021)		182,215		(12,095)		193,794
Total	$	(2,797)	$	149,164	$	(115,288)	$	1,390,575	$	(118,085)	$	1,539,739

Schedule of Amortized Cost and Fair Value of Securities by Contractual Maturities

As of September 30, 2025, the amortized cost and fair value of securities, by contractual maturities, are summarized below. Contractual maturities versus actual maturities may differ due to the effect of prepayments.


As of September 30, 2025 Year of Maturity (dollars in thousands)	Amortized Cost		Estimated Fair Value
2026	$	549,540	$	536,223
2027	99,322		98,356
2038	63		64
2039	521		516
2042	1,850		1,618
2043	3,542		3,214
2044	3,958		3,645
2045	4,268		3,840
2046	6,590		5,840
2047	6,078		5,425
2048	1,659		1,502
2049	13,829		12,379
2050	95,952		77,149
2051	136,536		108,674
2052	52,155		46,496
2053	295,220		296,378
2054	127,043		123,903
2055	233,104		234,952
2056	175,781		180,369
2058	34,132		35,241
Total	$	1,841,143	$	1,775,784