
	December 31, 2021
	Amortized Cost		Gross Unrealized				Estimated Fair Value
(in thousands)			Gains		Losses
U.S. government sponsored enterprise debt securities	$	443,892	$	9,319	$	(2,438)	$	450,773
Corporate debt securities	348,576		10,143		(929)		357,790
U.S. government agency debt securities	362,323		1,953		(2,370)		361,906
U.S. treasury securities	2,501		1		—		2,502
Municipal bonds	2,252		96		—		2,348

Total debt securities available for sale (1)	$	1,159,544	$	21,512	$	(5,737)	$	1,175,319

(1)As of December 31, 2021, includes residential and commercial mortgage-backed securities with amortized cost of $654.7 million and $123.5 million, respectively, and fair value of $661.3 million and $123.8 million, respectively.


	December 31, 2020
	Amortized Cost		Gross Unrealized				Estimated Fair Value
(in thousands)			Gains		Losses
U.S. government sponsored enterprise debt securities	$	640,796	$	21,546	$	(1,007)	$	661,335
Corporate debt securities	292,033		10,787		(1,106)		301,714
U.S. government agency debt securities	202,135		4,458		(2,015)		204,578
Municipal bonds	50,309		4,635		—		54,944

U.S. treasury securities	2,505		7		—		2,512
Total debt securities available for sale (1)	$	1,187,778	$	41,433	$	(4,128)	$	1,225,083

(1)As of December 31, 2020, includes residential and commercial mortgage-backed securities with amortized cost of $647.0 million and $123.9 million, respectively, and fair value of $666.7 million and $128.4 million, respectively.

The Company had no investments in foreign sovereign debt securities at December 31, 2021 and 2020. The Company had investments in foreign corporate debt securities available for sale of $12.5 million and $17.1 million at December 31, 2021 and 2020, respectively.

In the years ended December 31, 2021 and 2020, proceeds from sales, redemptions and calls, gross realized gains, gross realized losses of debt securities available for sale were as follows:


	Years Ended December 31
(in thousands)	2021		2020
Proceeds from sales, redemptions and calls of debt securities available for sale	$	114,923	$	421,175

Gross realized gains	4,307		25,692
Gross realized losses	(33)		(147)
Realized gains, net	$	4,274	$	25,545

The Company’s investment in debt securities available for sale with unrealized losses that are deemed temporary, aggregated by length of time that individual securities have been in a continuous unrealized loss position, are summarized below:


	December 31, 2021
	Less Than 12 Months				12 Months or More				Total
(in thousands)	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
U.S. government sponsored enterprise debt securities	$	54,562	$	(1,434)	$	25,526	$	(1,004)	$	80,088	$	(2,438)
Corporate debt securities	52,672		(259)		10,286		(670)		62,958		(929)
U.S. government agency debt securities	200,051		(1,177)		52,109		(1,193)		252,160		(2,370)



	$	307,285	$	(2,870)	$	87,921	$	(2,867)	$	395,206	$	(5,737)


	December 31, 2020
	Less Than 12 Months				12 Months or More				Total
(in thousands)	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
U.S. government sponsored enterprise debt securities	$	71,825	$	(661)	$	14,472	$	(346)	$	86,297	$	(1,007)
U.S. government agency debt securities	9,254		(62)		80,964		(1,953)		90,218		(2,015)

Corporate debt securities	31,777		(1,106)		—		—		31,777		(1,106)


	$	112,856	$	(1,829)	$	95,436	$	(2,299)	$	208,292	$	(4,128)

At December 31, 2021 and 2020, the Company held certain debt securities issued or guaranteed by the U.S. government and U.S. government-sponsored entities and agencies. The Company believes these issuers present little credit risk. The Company considers these securities are not other-than-temporarily impaired because the decline in fair value is attributable to changes in interest rates and investment securities markets, generally, and not credit quality. The Company does not intend to sell these debt securities and it is more likely than not that it will not be required to sell the securities before their anticipated recovery.

Unrealized losses on corporate debt securities are attributable to changes in interest rates and investment securities markets, generally, and as a result, temporary in nature. The Company considers these securities are not other-than-temporarily impaired because the issuers of these debt securities are high quality and present little credit risk. The Company does not intend to sell these investments and it is more likely than not that it will not be required to sell these investments before their anticipated recovery.


	December 31, 2021
	Amortized Cost		Gross Unrealized				Estimated Fair Value
(in thousands)			Gains		Losses
U.S. government agency debt securities	$	66,307	$	62	$	(363)	$	66,006
U.S. government sponsored enterprise debt securities	51,868		1,581		(378)		53,071
Total debt securities held to maturity (1)	$	118,175	$	1,643	$	(741)	$	119,077

(1)As of December 31, 2021, includes residential and commercial mortgage-backed securities with amortized cost of $89.4 million and $28.8 million, respectively, and fair value of $88.7 million and $30.4 million, respectively.


	December 31, 2020
	Amortized Cost		Gross Unrealized				Estimated Fair Value
(in thousands)			Gains		Losses
U.S. government agency debt securities	$	28,676	$	809	$	—	$	29,485
U.S. government sponsored enterprise debt securities	29,451		2,178		—		31,629
Total debt securities held to maturity (1)	$	58,127	$	2,987	$	—	$	61,114

(1)As of December 31, 2020, includes residential and commercial mortgage-backed securities with amortized cost of $28.7 million and $29.5 million, respectively, and fair value of $29.5 million and $31.6 million, respectively.

The Company’s investment in debt securities held to maturity with unrealized losses that are deemed temporary, aggregated by length of time that individual securities have been in a continuous unrealized loss position, are summarized below:


	December 31, 2021
	Less Than 12 Months				12 Months or More				Total
(in thousands)	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
U.S. government agency debt securities	$	61,037	$	(363)	$	—	$	—	$	61,037	$	(363)
U.S. government sponsored enterprise debt securities	22,669		(378)		—		—		22,669		(378)
	$	83,706	$	(741)	$	—	$	—	$	83,706	$	(741)


	Available for Sale				Held to Maturity
(in thousands)	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Within 1 year	$	32,439	$	32,706	$	—	$	—
After 1 year through 5 years	115,340		116,975		9,343		9,293
After 5 years through 10 years	280,303		290,249		11,189		11,672
After 10 years	731,462		735,389		97,643		98,112

	$	1,159,544	$	1,175,319	$	118,175	$	119,077

Actual maturities of debt securities available for sale and held to maturity may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without prepayment penalties.

Equity securities with readily available fair value not held for trading consist of mutual funds with an original cost of $0.3 million and $24.0 million, and fair value of $0.3 million and $24.3 million as of December 31, 2021 and 2020, respectively. These equity securities have no stated maturities. During 2021, the Company recognized a loss of $42 thousand on the sale of a mutual fund with a fair value of $23.4 million at the time of the sale. In addition, the Company recognized unrealized losses and gains of $0.6 million and $0.5 million during the years ended December 31, 2021 and 2020, respectively, related to the change in fair value of mutual funds.

As of December 31, 2021 and 2020, the Company had $142.8 million and $188.6 million, respectively, in securities pledged as collateral. These securities were pledged to secure advances from the Federal Home Loan Bank, public funds and for other purposes as permitted by law.