v3.24.1.u1
Investments (Tables)
 3 Months Ended
Mar. 31, 2024
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 March 31, 2024
(dollars in thousands)		Amortized Cost
Allowance for credit losses(1)
Gross Unrealized GainsGross Unrealized LossesEstimated Fair Value
Available-for-sale:
Mortgage-backed securities$485,026 $— $353 $(71,171)$414,208 
Utah Housing Corporation bonds3,201 — — (292)2,909 
U.S. government-sponsored enterprises and Treasuries1,396,341 — — (63,613)1,332,728 
Other securities538,615 — 2,385 (19,737)521,263 
Total $2,423,183 $— $2,738 $(154,813)$2,271,108 
As of December 31, 2023
(dollars in thousands)		Amortized Cost
Allowance for credit losses(1)
Gross Unrealized GainsGross Unrealized LossesEstimated Fair Value
Available-for-sale:
Mortgage-backed securities$468,204 $— $703 $(62,480)$406,427 
Utah Housing Corporation bonds3,408 — — (279)3,129 
U.S. government-sponsored enterprises and Treasuries1,645,609 — — (66,870)1,578,739 
Other securities446,763 — 603 (24,039)423,327 
Total $2,563,984 $— $1,306 $(153,668)$2,411,622 
(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 months12 months or moreTotal
Gross
Unrealized
Losses		Estimated
Fair Value		Gross
Unrealized
Losses		Estimated
Fair Value		Gross
Unrealized
Losses		Estimated
Fair Value
As of March 31, 2024:
Mortgage-backed securities$(1,650)$98,678 $(69,521)$286,434 $(71,171)$385,112 
Utah Housing Corporation bonds— — (292)2,909 (292)2,909 
U.S. government-sponsored enterprises and Treasuries— — (63,613)1,232,727 (63,613)1,232,727 
Other securities(1,226)63,358 (18,511)201,538 (19,737)264,896 
Total$(2,876)$162,036 $(151,937)$1,723,608 $(154,813)$1,885,644 
As of December 31, 2023:
Mortgage-backed securities$(531)$51,391 $(61,949)$300,318 $(62,480)$351,709 
Utah Housing Corporation bonds— — (279)3,129 (279)3,129 
U.S. government-sponsored enterprises and Treasuries— — (66,870)1,578,739 (66,870)1,578,739 
Other securities(2,221)90,725 (21,818)241,253 (24,039)331,978 
Total$(2,752)$142,116 $(150,916)$2,123,439 $(153,668)$2,265,555 
Schedule of Amortized Cost and Fair Value of Securities by Contractual Maturities
As of March 31, 2024, 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 March 31, 2024
Year of Maturity
(dollars in thousands)
Amortized CostEstimated Fair Value
2024449,757 442,325 
2025299,063 290,830 
2026548,807 504,757 
202798,713 94,816 
203868 68 
2039581 566 
20422,252 1,928 
20434,079 3,626 
20444,467 4,047 
20454,898 4,300 
20467,451 6,498 
20477,409 6,533 
20482,008 1,923 
204915,238 13,344 
2050106,282 83,558 
2051153,057 119,243 
205251,825 44,160 
2053242,958 235,101 
205486,866 79,516 
205582,255 79,089 
2056210,422 209,947 
205844,727 44,933 
Total$2,423,183 $2,271,108