Investment Securities (Tables)

6 Months Ended

Jun. 30, 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 June 30, 2022 and December 31, 2021 were as follows (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Fair Value
June 30, 2022
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	261,387	$	8	$	(24,548	)	$	236,847
Obligations of states and political subdivisions		385,688		678		(58,544	)		327,822
Mortgage-backed securities: GSE residential		793,979		37		(95,673	)		698,343
Other securities		89,512		29		(2,605	)		86,936
Total available-for-sale	$	1,530,566	$	752	$	(181,370	)	$	1,349,948
Held-to-maturity:
Other investments	$	2,972	$	—	$	—		$	2,972
Total held-to-maturity	$	2,972	$	—	$	—		$	2,972
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 investments		2,029		—		—			2,029
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	7,030	$	5	$	—		$	7,035

Realized Gains and Losses From Sale of Securities

Realized gains and losses resulting from sales of securities were as follows during the three and six months ended June 30, 2022 and 2021 (in thousands):

	Three months June 30,				Six months June 30,
	2022		2021		2022		2021
Gross gains	$	2	$	73	$	2	$	77
Gross losses		—		—		—		—

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 June 30, 2022 and the weighted average yield for each range of maturities (dollars in thousands):

	One year or less			After 1 through 5 years			After 5 through 10 years			After ten years			Total
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	170,756		$	56,145		$	9,946		$	—		$	236,847
Obligations of state and political subdivisions		22,218			95,449			209,021			1,134			327,822
Mortgage-backed securities: GSE residential		6,114			113,107			570,106			9,016			698,343
Other securities		19,291			66,746			899			—			86,936
Total available-for-sale investments	$	218,379		$	331,447		$	789,972		$	10,150		$	1,349,948
Weighted average yield		1.54	%		2.46	%		1.77	%		1.69	%		1.89	%
Full tax-equivalent yield		1.65	%		2.75	%		1.95	%		1.82	%		2.09	%
Held to maturity:
Other investments	$	—		$	—		$	—		$	2,972		$	2,972
Total held-to-maturity	$	—		$	—		$	—		$	2,972		$	2,972
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 June 30, 2022 and December 31, 2021 (in thousands):

	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
June 30, 2022
Available-for-sale:
U.S. Treasury securities and obligations of U.S. government corporations and agencies	$	121,758	$	(8,930	)	$	111,991	$	(15,618	)	$	233,749	$	(24,548	)
Obligations of states and political subdivisions		253,771		(55,918	)		7,466		(2,626	)		261,237		(58,544	)
Mortgage-backed securities: GSE residential		505,673		(62,477	)		188,576		(33,196	)		694,249		(95,673	)
Other securities		66,927		(2,529	)		2,489		(76	)		69,416		(2,605	)
Total	$	948,129	$	(129,854	)	$	310,522	$	(51,516	)	$	1,258,651	$	(181,370	)
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	)