Investment Securities (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Schedule of Amortized Cost of Securities and Fair Values

The following tables summarize the amortized cost, allowance for credit losses and fair value of the available-for-sale debt securities and the corresponding amounts of unrealized gains and losses recognized in accumulated other comprehensive loss at December 31, 2023 and 2022:  

	December 31, 2023
	Amortized cost		Gross unrealized gains		Gross unrealized losses		Allowance for credit losses for investments		Fair Value
Investment Securities
Available-for-sale debt securities
U.S. government agency securities	$	204,663	$	470	$	(1,177)	$	—	$	203,956
Mortgage-backed securities - residential	1,057,389		—		(160,418)		—		896,971
Mortgage-backed securities - commercial	18,186		—		(1,225)		—		16,961
Municipal securities	263,312		370		(21,419)		—		242,263
U.S. Treasury securities	111,729		—		(3,233)		—		108,496
Corporate securities	3,500		—		(174)		—		3,326
Total	$	1,658,779	$	840	$	(187,646)	$	—	$	1,471,973

	December 31, 2022
	Amortized cost		Gross unrealized gains		Gross unrealized losses		Allowance for credit losses for investments		Fair Value
Investment Securities
Available-for-sale debt securities
U.S. government agency securities	$	45,167	$	—	$	(5,105)	$	—	$	40,062
Mortgage-backed securities - residential	1,224,522		—		(190,329)		—		1,034,193
Mortgage-backed securities - commercial	19,209		—		(1,565)		—		17,644
Municipal securities	295,375		458		(31,413)		—		264,420
U.S. Treasury securities	113,301		—		(5,621)		—		107,680
Corporate securities	8,000		—		(813)		—		7,187
Total	$	1,705,574	$	458	$	(234,846)	$	—	$	1,471,186

Schedule of Gross Unrealized Losses

The following tables show gross unrealized losses for which an allowance for credit losses has not been recorded at December 31, 2023 and 2022, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position:

	December 31, 2023
	Less than 12 months				12 months or more				Total
	Fair Value		Gross Unrealized Loss		Fair Value		Gross Unrealized Loss		Fair Value		Gross Unrealized Loss
U.S. government agency securities	$	25,923	$	(21)	$	14,040	$	(1,156)	$	39,963	$	(1,177)
Mortgage-backed securities - residential	—		—		896,971		(160,418)		896,971		(160,418)
Mortgage-backed securities - commercial	—		—		16,961		(1,225)		16,961		(1,225)
Municipal securities	14,480		(148)		188,669		(21,271)		203,149		(21,419)
U.S. Treasury securities	—		—		108,496		(3,233)		108,496		(3,233)
Corporate securities	—		—		3,326		(174)		3,326		(174)
Total	$	40,403	$	(169)	$	1,228,463	$	(187,477)	$	1,268,866	$	(187,646)

	December 31, 2022
	Less than 12 months				12 months or more				Total
	Fair Value		Gross Unrealized Loss		Fair Value		Gross Unrealized Loss		Fair Value		Gross Unrealized Loss
U.S. government agency securities	$	23,791	$	(2,802)	$	16,271	$	(2,303)	$	40,062	$	(5,105)
Mortgage-backed securities - residential	316,656		(32,470)		717,537		(157,859)		1,034,193		(190,329)
Mortgage-backed securities - commercial	11,104		(968)		6,540		(597)		17,644		(1,565)
Municipal securities	196,419		(26,811)		36,726		(4,602)		233,145		(31,413)
U.S. Treasury securities	94,248		(4,122)		13,432		(1,499)		107,680		(5,621)
Corporate securities	4,008		(492)		3,179		(321)		7,187		(813)
Total	$	646,226	$	(67,665)	$	793,685	$	(167,181)	$	1,439,911	$	(234,846)

Schedule of Amortized Cost and Fair Value of Debt Securities by Contractual Maturity

	December 31,
	2023				2022
	Available-for-sale				Available-for-sale
	Amortized cost		Fair value		Amortized cost		Fair value
Due in one year or less	$	64,776	$	64,279	$	4,277	$	4,225
Due in one to five years	75,996		71,801		161,556		152,181
Due in five to ten years	51,162		49,630		61,290		57,859
Due in over ten years	391,270		372,331		234,720		205,084
	583,204		558,041		461,843		419,349
Mortgage-backed securities - residential	1,057,389		896,971		1,224,522		1,034,193
Mortgage-backed securities - commercial	18,186		16,961		19,209		17,644
Total debt securities	$	1,658,779	$	1,471,973	$	1,705,574	$	1,471,186

Schedule of Sales and Other Dispositions of Available-for-Sale Securities

Sales and other dispositions of AFS debt securities were as follows:

	Years Ended December 31,
	2023		2022		2021
Proceeds from sales	$	100,463	$	1,218	$	8,855
Proceeds from maturities, prepayments and calls	128,206		204,748		296,256
Gross realized gains	45		4		127
Gross realized losses	14,119		3		1