Securities (Tables)

3 Months Ended

Mar. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Summary of Amortized Cost and Fair Values of Securities Available-for-sale, and Held to Maturity

The following tables summarize the amortized cost and fair values of securities available-for-sale and securities held-to-maturity as of the dates shown and the corresponding amounts of gross unrealized gains and losses:

March 31, 2022	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Available-for-sale
U.S. Treasury Notes	$	24,875	$	4	$	(654	)	$	24,225
U.S. Government agencies		149,164		328		(9,252	)		140,240
Obligations of states, municipalities, and    political subdivisions		83,786		512		(2,170	)		82,128
Residential mortgage-backed securities
Agency		758,179		21		(57,343	)		700,857
Non-agency		140,350		—		(9,926	)		130,424
Commercial mortgage-backed securities
Agency		206,203		25		(16,535	)		189,693
Corporate securities		65,798		488		(1,144	)		65,142
Asset-backed securities		36,796		10		(147	)		36,659
Total	$	1,465,151	$	1,388	$	(97,171	)	$	1,369,368

March 31, 2022	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Held-to-maturity
Obligations of states, municipalities, and    political subdivisions	$	3,882	$	24	$	—	$	3,906
Total	$	3,882	$	24	$	—	$	3,906

December 31, 2021	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Available-for-sale
U.S. Treasury Notes	$	18,447	$	37	$	(8	)	$	18,476
U.S. Government agencies		141,096		661		(2,367	)		139,390
Obligations of states, municipalities, and    political subdivisions		86,454		3,238		(56	)		89,636
Residential mortgage-backed securities
Agency		756,549		2,122		(15,015	)		743,656
Non-agency		146,499		4		(1,267	)		145,236
Commercial mortgage-backed securities
Agency		214,417		2,795		(3,661	)		213,551
Corporate securities		65,814		1,586		(54	)		67,346
Asset-backed securities		37,206		49		(4	)		37,251
Total	$	1,466,482	$	10,492	$	(22,432	)	$	1,454,542

December 31, 2021	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Held-to-maturity
Obligations of states, municipalities, and political    subdivisions	$	3,885	$	107	$	—	$	3,992
Total	$	3,885	$	107	$	—	$	3,992

Summary of Gross Unrealized Losses and Fair Values, Aggregated by Investment Category and Length of Individual Securities Continuous Unrealized Loss Position Available-for-sale and Held to Maturity

Gross unrealized losses and fair values, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of March 31, 2022 and December 31, 2021, are summarized as follows:

			Less than 12 Months					12 Months or Longer					Total
March 31, 2022	# of Securities		Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Available-for-sale
U.S. Treasury Notes		4	$	22,223	$	(654	)	$	—	$	—		$	22,223	$	(654	)
U.S. Government agencies		15		43,883		(1,915	)		74,242		(7,337	)		118,125		(9,252	)
Obligations of states,    municipalities and political    subdivisions		25		42,934		(2,170	)		—		—			42,934		(2,170	)
Residential mortgage-backed    securities
Agency		93		229,246		(11,442	)		469,295		(45,901	)		698,541		(57,343	)
Non-agency		19		110,832		(7,854	)		19,592		(2,072	)		130,424		(9,926	)
Commercial mortgage-backed    securities
Agency		45		111,241		(6,766	)		69,134		(9,769	)		180,375		(16,535	)
Corporate securities		16		28,709		(1,144	)		—		—			28,709		(1,144	)
Asset-backed securities		6		31,961		(147	)		—		—			31,961		(147	)
Total		223	$	621,029	$	(32,092	)	$	632,263	$	(65,079	)	$	1,253,292	$	(97,171	)

			Less than 12 Months					12 Months or Longer					Total
December 31, 2021	# of Securities		Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Available-for-sale
U.S. Treasury Notes		1	$	9,946	$	(8	)	$	—	$	—		$	9,946	$	(8	)
U.S. Government agencies		10		64,585		(1,590	)		19,223		(777	)		83,808		(2,367	)
Obligations of states, municipalities and    political subdivisions		3		9,507		(56	)		—		—			9,507		(56	)
Residential mortgage-backed securities
Agency		51		612,280		(13,894	)		25,412		(1,121	)		637,692		(15,015	)
Non-agency		14		96,372		(1,257	)		761		(10	)		97,133		(1,267	)
Commercial mortgage-backed securities
Agency		19		64,473		(1,994	)		37,063		(1,667	)		101,536		(3,661	)
Corporate securities		3		7,502		(54	)		—		—			7,502		(54	)
Asset-backed securities		3		15,978		(4	)		—		—			15,978		(4	)
Total		104	$	880,643	$	(18,857	)	$	82,459	$	(3,575	)	$	963,102	$	(22,432	)

Summary of Proceeds From Sales of Securities Available-for-sale and Associated Gains and Losses

The proceeds from all sales of securities available-for-sale, and the associated gains and losses on sales and calls of securities, for the three months ended March 31, 2022 and 2021 are listed below:

	For the Three Months Ended
	March 31,
	2022		2021
Proceeds	$	—	$	89,301
Gross gains		—		1,626
Gross losses		—		164

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

At March 31, 2022, the amortized cost and fair value of debt securities are shown by contractual maturity. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately.

	Amortized Cost		Fair Value
Available-for-sale
Due in one year or less	$	12,011	$	12,051
Due from one to five years		71,166		69,792
Due from five to ten years		202,902		196,070
Due after ten years		74,340		70,481
Mortgage-backed securities		1,104,732		1,020,974
Total	$	1,465,151	$	1,369,368
Held-to-maturity
Due in one year or less	$	1,174	$	1,182
Due from one to five years		2,708		2,724
Total	$	3,882	$	3,906