SECURITIES

9 Months Ended

Sep. 30, 2021

Investments, Debt and Equity Securities [Abstract]

Amortized cost and estimated fair value of securities available for sale are as follows (in thousands):


	September 30, 2021
	Amortized Cost		Unrealized Gains		Unrealized Losses		Estimated Fair Value
U.S. Treasury notes and bonds	$	40,499	$	—	$	162	$	40,337
Mortgage-backed securities, residential	588,555		5,397		7,826		586,126
Obligations of states and political subdivisions	40,331		2,021		—		42,352
Corporate bonds and notes	17,000		116		55		17,061
SBA loan pools	75,612		398		355		75,655

Total	$	761,997	$	7,932	$	8,398	$	761,531


	December 31, 2020
	Amortized Cost		Unrealized Gains		Unrealized Losses		Estimated Fair Value

Mortgage-backed securities, residential	$	458,245	$	9,822	$	201	$	467,866

Obligations of states and political subdivisions	40,662		2,743		—		43,405
Corporate bonds and notes	9,000		47		12		9,035
SBA loan pools	34,455		42		192		34,305


Total	$	542,362	$	12,654	$	405	$	554,611

Amortized cost and estimated fair value of securities held to maturity are as follows (in thousands):


	September 30, 2021
	Amortized Cost		Unrecognized Gains		Unrecognized Losses		Estimated Fair Value
Obligations of states and political subdivisions	$	1,300	$	—	$	—	$	1,300
Time deposits with other financial institutions	1,883		11		—		1,894
Total	$	3,183	$	11	$	—	$	3,194


	December 31, 2020
	Amortized Cost		Unrecognized Gains		Unrecognized Losses		Estimated Fair Value
Obligations of states and political subdivisions	$	326	$	—	$	—	$	326
Time deposits with other financial institutions	2,143		32		—		2,175
Total	$	2,469	$	32	$	—	$	2,501

The amortized cost and estimated fair value of debt securities are shown below by expected 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 (in thousands):


	September 30, 2021
	Available for Sale				Held to Maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Within one year	$	686	$	689	$	1,523	$	1,532
After one, but within five years	75,962		77,278		860		862
After five, but within ten years	20,712		21,285		800		800
After ten years	470		498		—		—
	97,830		99,750		3,183		3,194
Mortgage-backed securities, residential	588,555		586,126		—		—

SBA loan pools	75,612		75,655		—		—
Total	$	761,997	$	761,531	$	3,183	$	3,194

There were no proceeds from sales and calls of securities resulting in gains or losses for the three and nine month periods ended September 30, 2021 and 2020.

The following tables summarize the investment securities available for sale with unrealized losses at September 30, 2021 and December 31, 2020 by aggregated major security type and length of time in a continuous unrealized loss position (in thousands):


	Less than 12 months				12 months or longer				Total
September 30, 2021	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. Treasury notes and bonds	$	24,819	$	162	$	—	$	—	$	24,819	$	162
Mortgage-backed securities, residential	383,380		7,707		4,146		119		387,526		7,826

Corporate bonds and notes	2,979		21		2,966		34		5,945		55
SBA loan pools	39,140		283		6,273		72		45,413		355

Total temporarily impaired securities	$	450,318	$	8,173	$	13,385	$	225	$	463,703	$	8,398


	Less than 12 months				12 months or longer				Total
December 31, 2020	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses

Mortgage-backed securities, residential	$	70,037	$	200	$	970	$	1	$	71,007	$	201

Corporate bonds and notes	2,988		12		—		—		2,988		12
SBA loan pools	15,245		156		3,636		36		18,881		192
Total temporarily impaired securities	$	88,270	$	368	$	4,606	$	37	$	92,876	$	405

Other-Than-Temporary Impairment

As of September 30, 2021, the majority of the Corporation's unrealized losses in the investment securities portfolio related to mortgage-backed securities. At September 30, 2021, all of the unrealized losses related to mortgage-backed securities were issued by U.S. government sponsored entities, Fannie Mae and Freddie Mac. Because the decline in fair value is attributable to changes in interest rates and not credit quality, and because the Corporation does not have the intent to sell these securities and it is not likely that it will be required to sell these securities before their anticipated recovery, the Corporation does not consider these securities to be other-than-temporarily impaired at September 30, 2021.