Investment Securities (Tables)

12 Months Ended

Dec. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Available for Sale and Held For Maturity Securities

The amortized cost, gross unrealized gains and losses and estimated fair values for available-for-sale and held-to-maturity securities by major security type at December 31, 2022 and 2021 were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		(Losses)			Fair Value
December 31, 2022
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	252,934	$	—	$	(32,407	)	$	220,527
Obligations of states and political subdivisions		347,409		134		(59,845	)		287,698
Mortgage-backed securities: GSE residential		744,636		3		(116,759	)		627,880
Other securities		87,393		6		(4,519	)		82,880
Total available-for-sale	$	1,432,372	$	143	$	(213,530	)	$	1,218,985
Held-to-maturity:
Other securities	$	2,954	$	—	$	—		$	2,954
Total held-to-maturity	$	2,954	$	—	$	—		$	2,954
December 31, 2021
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	208,598	$	80	$	(4,863	)	$	203,815
Obligations of states and political subdivisions		383,991		12,123		(657	)		395,457
Mortgage-backed securities: GSE residential		799,456		4,292		(12,710	)		791,038
Other securities		30,546		671		(105	)		31,112
Total available-for-sale	$	1,422,591	$	17,166	$	(18,335	)	$	1,421,422
Held-to-maturity:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	5,001	$	5	$	—		$	5,006
Other securities		2,029		—		—			2,029
Total held-to-maturity	$	7,030	$	5	$	—		$	7,035

Proceeds From Sales of Available for Sale Investment Securities, Realized Gains and Losses and Income Tax Expense

Proceeds from sales of available-for-sale investment securities, realized gains and losses and income tax expense were as follows during the years ended December 31, 2022, 2021, and 2020 (in thousands):

	2022			2021		2020
Proceeds from sales	$	36,257		$	611	$	9,061
Gross gains		202			124		1,132
Gross losses		(169	)		—		(26	)
Income tax expense		(10	)		36		321

Investments Classified by Contractual Maturity Date

The following table indicates the expected maturities of investment securities classified as available-for-sale presented at fair value, and held-to-maturity presented at amortized cost at December 31, 2022 and the weighted average yield for each range of maturities (dollars in thousands):

	One			After 1			After 5
	year or			through			through			After
	less			5 years			10 years			ten years			Total
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	161,688		$	49,187		$	9,652		$	—		$	220,527
Obligations of state and political subdivisions		19,446			76,847			190,232			1,173			287,698
Mortgage-backed securities: GSE residential		4,762			97,333			524,164			1,621			627,880
Other securities		20,636			60,533			1,711			—			82,880
Total available-for-sale	$	206,532		$	283,900		$	725,759		$	2,794		$	1,218,985
Weighted average yield		1.56	%		2.44	%		1.75	%		2.92	%		1.87	%
Full tax equivalent yield		1.66	%		2.70	%		1.92	%		3.44	%		2.05	%
Held-to-maturity:
Other securities	$	—		$	—		$	—		$	2,954		$	2,954
Total held-to-maturity	$	—		$	—		$	—		$	2,954		$	2,954
Weighted average yield		—	%		—	%		—	%		—	%		—	%
Full tax equivalent yield		—	%		—	%		—	%		—	%		—	%

Fair Value of Investments with Sustained Gross Unrealized Losses

The following table presents the aging of gross unrealized losses and fair value by investment category as of December 31, 2022 and 2021 (in thousands):

	Less than 12 months					12 months or more					Total
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Losses			Value		Losses			Value		Losses
December 31, 2022
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	57,007	$	(3,493	)	$	163,520	$	(28,914	)	$	220,527	$	(32,407	)
Obligations of states and political subdivisions		220,102		(43,221	)		45,419		(16,624	)		265,521		(59,845	)
Mortgage-backed securities: GSE residential		165,966		(19,859	)		461,446		(96,900	)		627,412		(116,759	)
Other securities		64,676		(3,675	)		6,698		(844	)		71,374		(4,519	)
Total	$	507,751	$	(70,248	)	$	677,083	$	(143,282	)	$	1,184,834	$	(213,530	)
December 31, 2021
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	48,316	$	(1,927	)	$	139,846	$	(2,936	)	$	188,162	$	(4,863	)
Obligations of states and political subdivisions		61,535		(657	)		—		—			61,535		(657	)
Mortgage-backed securities: GSE residential		562,699		(11,019	)		46,504		(1,691	)		609,203		(12,710	)
Other securities		7,976		(105	)		—		—			7,976		(105	)
Total	$	680,526	$	(13,708	)	$	186,350	$	(4,627	)	$	866,876	$	(18,335	)

Maturities of Investment Securities

Maturities of investment securities were as follows at December 31, 2022 (in thousands):

	Amortized		Estimated
	Cost		Fair Value
Available-for-sale:
Due in one year or less	$	228,998	$	201,770
Due after one-five years		203,048		186,567
Due after five-ten years		254,473		201,595
Due after ten years		1,217		1,173
		687,736		591,105
Mortgage-backed securities: GSE residential		744,636		627,880
Total available-for-sale	$	1,432,372	$	1,218,985
Held-to-maturity:
Due in one year or less	$	—	$	—
Due after ten years		2,954		2,954
Total held-to-maturity	$	2,954	$	2,954