
December 31, 2022	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance for		Estimated Fair Value
(dollars in thousands)							Credit Losses
Investment securities available-for-sale:
U.S. treasury bonds	$	49,793	$	—	$	(3,466)	$	—	$	46,327
U.S. agency securities	747,777		—		(78,049)		—		669,728
Residential mortgage-backed securities	937,557		18		(117,072)		—		820,503
Commercial mortgage-backed securities	56,071		—		(5,858)		—		50,213
Municipal bonds	10,700		45		(658)		—		10,087
Corporate bonds	2,000		—		(175)		(17)		1,808
Total available-for-sale securities	$	1,803,898	$	63	$	(205,278)	$	(17)	$	1,598,666


December 31, 2022	Amortized Cost		Gross Unrecognized Gains		Gross Unrecognized Losses			Estimated
(dollars in thousands)							Fair Value
Investment securities held-to-maturity:


Residential mortgage-backed securities	$	741,057	$	—	$	(88,390)		$	652,667
Commercial mortgage-backed securities	92,557		—		(11,993)			80,564
Municipal bonds	128,273		—		(12,092)			116,181
Corporate bonds	132,253		—		(12,958)			119,295
	1,094,140		$	—	$	(125,433)		$	968,707
Allowance for credit losses	(766)
Total held-to-maturity securities, net of ACL	$	1,093,374


December 31, 2021	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance for		Estimated Fair Value
(dollars in thousands)							Credit Losses
Investment securities available-for-sale:
U.S. treasury bonds	$	49,693	$	22	$	(257)	$	—	$	49,458
U.S. agency securities	629,273		736		(7,622)		—		622,387
Residential mortgage-backed securities	1,634,421		4,053		(20,447)		—		1,618,027
Commercial mortgage-backed securities	58,352		1,644		(350)		—		59,646
Municipal bonds	141,916		3,865		(347)		(3)		145,431
Corporate bonds	129,012		648		(584)		(617)		128,459
	$	2,642,667	$	10,968	$	(29,607)	$	(620)	$	2,623,408

In addition, at December 31, 2022 and December 31, 2021, the Company held $65.1 million and $34.2 million in non marketable equity securities, respectively, in a combination of FRB and FHLB stocks, which are required to be held for regulatory purposes. The stocks are both carried at cost, classified as restricted securities, and periodically evaluated for impairment based on ultimate recovery of par value.

The Company reassessed classification of certain investments in the first quarter of 2022 and, effective March 31, 2022, it transferred a total of $1.1 billion of mortgage-backed securities, municipal bonds and corporate bonds from available-for-sale to held-to-maturity securities, including $237.0 million of securities acquired in the first quarter of 2022 for which its intention to hold to maturity was finalized. At the time of transfer, the Company reversed the allowance for credit losses associated with the available-for-sale securities through the provision for credit losses. The securities were transferred at their amortized cost basis, net of any remaining unrealized gain or loss reported in accumulated other comprehensive income. The related unrealized loss of $66.2 million was included in other comprehensive loss at the time of transfer and, as of December 31, 2022, $59.1 million remains in accumulated other comprehensive loss, to be amortized out through interest income as a yield adjustment over the remaining term of the securities. No gain or loss was recorded at the time of transfer. Subsequent to transfer, the allowance for credit losses on these securities was evaluated under the accounting policy for held-to-maturity securities.

Accrued interest receivable on investment securities totaled $7.8 million and $6.0 million at December 31, 2022 and December 31, 2021, respectively. The accrued interest on investment securities is excluded from the amortized cost of the securities and is reported in other assets in the Consolidated Balance Sheets.

However, as of December 31, 2022 and 2021, the Company determined that certain of the unrealized loss positions in available-for-sale and held-to-maturity corporate and municipal bonds were evidence of expected credit losses. An allowance for credit losses of $17 thousand was recorded for AFS securities and $766 thousand for HTM securities in 2022. The weighted average duration of debt securities, which comprise 100% of total investment securities, is 4.8 years. Provision recorded for credit losses for securities was $163 thousand as of December 31, 2022. If quoted prices are not available, fair value is measured using independent pricing models or other model-based valuation techniques such as the present value of future cash flows, adjusted for the security’s credit rating, prepayment assumptions and other factors such as credit loss assumptions. The Company does not intend to sell the held-to-maturity investments and it is more likely than not that the Company will not have to sell the securities before recovery of its amortized cost basis, which may be at maturity.


Investment securities available-for-sale:		Less than 12 Months				12 Months or Greater				Total
December 31, 2022	Number of Securities	Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses
(dollars in thousands)
U.S. treasury bonds	2	$	—	$	—	$	46,327	$	(3,466)	$	46,327	$	(3,466)
U.S. agency securities	85	490,699		(58,437)		179,029		(19,612)		669,728		(78,049)
Residential mortgage-backed securities	157	3,994		—		808,697		(117,073)		812,691		(117,073)
Commercial mortgage-backed securities	14	471		(2)		49,742		(5,855)		50,213		(5,857)
Municipal bonds	1	—		—		8,299		(658)		8,299		(658)
Corporate bonds	1	—		—		1,825		(175)		1,825		(175)
	260	$	495,164	$	(58,439)	$	1,093,919	$	(146,839)	$	1,589,083	$	(205,278)


Investment securities held-to-maturity:		Less than 12 Months				12 Months or Greater				Total
December 31, 2022	Number of Securities	Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses
(dollars in thousands)


Residential mortgage-backed securities	143	$	—	$	—	$	652,667	$	(88,390)	$	652,667	$	(88,390)
Commercial mortgage-backed securities	16	—		—		80,564		(11,993)		$	80,564	(11,993)
Municipal bonds	43	3,110		(45)		113,071		(12,047)		$	116,181	(12,092)
Corporate bonds	30	20,771		(3,183)		86,451		(9,775)		$	107,222	(12,958)
	232	$	23,881	$	(3,228)	$	932,753	$	(122,205)	$	956,634	$	(125,433)


Investment securities available-for-sale		Less than 12 Months				12 Months or Greater				Total
December 31, 2021	Number of Securities	Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses
(dollars in thousands)
U.S. treasury bonds	1	$	24,593	$	(257)	$	—	$	—	$	24,593	$	(257)
U.S. agency securities	64	452,966		(6,256)		68,977		(1,366)		521,943		(7,622)
Residential mortgage-backed securities	149	1,327,519		$	(16,841)	84,500		(3,606)		1,412,019		(20,447)
Commercial mortgage-backed securities	4	—		—		23,561		(350)		23,561		(350)
Municipal bonds	8	20,181		$	(347)	—		—		20,181		(347)
Corporate bonds	13	66,051		$	(584)	—		$	—	66,051		(584)
	239	$	1,891,310	$	(24,285)	$	177,038	$	(5,322)	$	2,068,348	$	(29,607)

The amortized cost and estimated fair value of investments available-for-sale at December 31, 2022 and 2021 by contractual maturity are shown in the table below. Expected maturities for residential mortgage-backed securities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.


Investment securities available-for-sale:	December 31, 2022				December 31, 2021
(dollars in thousands)	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
U.S. agency securities maturing:
One year or less	$	549,137	$	490,699	$	425,597	$	421,347
After one year through five years	111,742		100,297		141,537		140,785
Five years through ten years	73,886		68,180		62,092		60,255
After ten years	13,012		10,552
Residential mortgage-backed securities	937,557		820,503		1,634,468		1,618,027
Commercial mortgage-backed securities	56,071		50,213		58,352		59,646
Municipal bonds maturing:
One year or less	300		300		4,806		4,861
After one year through five years	1,444		1,488		25,457		26,816
Five years through ten years	8,956		8,299		97,945		99,960
After ten years	—		—		13,708		13,797
Corporate bonds maturing:
One year or less	—		—		18,924		18,991
After one year through five years	2,000		1,825		54,630		54,833
Five years through ten years	—		—		55,458		55,252
After ten years	—		—		—		—
U.S. treasury	49,793		46,327		49,693		49,458
	1,803,898		1,598,683		2,642,667		2,624,028
Allowance for credit losses	—		(17)		—		(620)
	$	1,803,898	$	1,598,666	$	2,642,667	$	2,623,408


Investment securities held-to-maturity:	December 31, 2022				December 31, 2021
(dollars in thousands)	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value




Residential mortgage-backed securities	$	741,057	$	652,667	$	—	$	—
Commercial mortgage-backed securities	92,557		80,564
Municipal bonds maturing:
One year or less	3,139		3,110		—		—
After one year through five years	35,579		33,743		—		—
Five years through ten years	77,262		67,945		—		—
After ten years	12,293		11,383		—		—
Corporate bonds maturing:
One year or less	23,954		20,771		—		—
After one year through five years	84,953		77,997		—		—
Five years through ten years	23,346		20,527		—		—


	1,094,140		968,707		—		—
Allowance for credit losses	(766)		—		—		—
	$	1,093,374	$	968,707	$	—	$	—

In 2022, gross realized gains on sales of investment securities were $18 thousand and gross realized losses on sales of investment securities were $187 thousand. In 2021, gross realized gains on sales of investment securities were $3.2 million and gross realized losses on sales of investment securities were $187 thousand. In 2020, gross realized gains on sales of investment securities were $1.9 million and gross realized losses on sales of investment securities were $46 thousand. Proceeds from sales and calls of investment securities for 2022, 2021 and 2020 were $14.6 million, $201.0 million and $124.1 million, respectively.

The carrying value of securities pledged as collateral for certain government deposits, securities sold under agreements to repurchase and certain lines of credit with correspondent banks at December 31, 2022 was $220.1 million and $261.0 million at December 31, 2021, which is well in excess of required amounts in order to operationally provide significant reserve amounts for new business. As of December 31, 2022 and December 31, 2021, there were no holdings of securities of any one issuer, other than the U.S. Government and U.S. agency securities, which exceeded ten percent of shareholders’ equity.