Investments (Tables)

3 Months Ended

Mar. 31, 2022

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, 2022 (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	$	400,647	$	—	$	74	$	(29,641)	$	371,080
Utah Housing Corporation bonds	4,926		—		—		(77)		4,849
U.S. government-sponsored enterprises and Treasuries	1,799,080		—		—		(63,830)		1,735,250
Other securities	235,551		—		—		(5,179)		230,372
Total	$	2,440,204	$	—	$	74	$	(98,727)	$	2,341,551
As of December 31, 2021 (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	$	376,313	$	—	$	1,857	$	(7,073)	$	371,097
Utah Housing Corporation bonds	6,943		—		18		—		6,961
U.S. government-sponsored enterprises and Treasuries	1,958,943		—		603		(11,893)		1,947,653
Other securities	193,369		—		439		(1,563)		192,245
Total	$	2,535,568	$	—	$	2,917	$	(20,529)	$	2,517,956

(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.

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 March 31, 2022:
Mortgage-backed securities	$	(12,056)	$	188,447	$	(17,585)	$	176,659	$	(29,641)	$	365,106
Utah Housing Corporation bonds	(77)		4,849		—		—		(77)		4,849
U.S. government-sponsored enterprises and Treasuries	(61,996)		1,647,055		(1,834)		63,176		(63,830)		1,710,231
Other securities	(3,266)		137,845		(1,913)		36,752		(5,179)		174,597
Total	$	(77,395)	$	1,978,196	$	(21,332)	$	276,587	$	(98,727)	$	2,254,783
As of December 31, 2021:
Mortgage-backed securities	$	(5,534)	$	261,404	$	(1,540)	$	36,587	$	(7,074)	$	297,991
Utah Housing Corporation bonds	—		—		—		—		—		—
U.S. government-sponsored enterprises and Treasuries	(11,892)		1,199,367		—		—		(11,892)		1,199,367
Other securities	(1,563)		132,884		—		—		(1,563)		132,884
Total	$	(18,989)	$	1,593,655	$	(1,540)	$	36,587	$	(20,529)	$	1,630,242

Amortized Cost and Fair Value of Securities by Contractual Maturities

As of March 31, 2022, 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, 2022 Year of Maturity (dollars in thousands)	Amortized Cost		Estimated Fair Value
2022	$	194,309	$	193,447
2023	162,595		159,383
2024	597,268		577,077
2025	297,077		293,021
2026	547,832		512,323
2038	73		76
2039	873		916
2042	2,912		2,768
2043	5,415		5,336
2044	7,015		6,959
2045	6,158		6,018
2046	9,374		9,085
2047	9,957		9,751
2048	2,427		2,437
2049	18,261		17,902
2050	127,490		116,445
2051	174,646		159,542
2052	40,972		38,693
2053	132,336		128,621
2054	103,214		101,751
Total	$	2,440,204	$	2,341,551