Securities

9 Months Ended

Sep. 30, 2020

Investments Debt And Equity Securities [Abstract]

Securities

(3) SECURITIES

The following table summarizes the amortized cost and estimated fair values of debt securities held for investment:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
September 30, 2020	(Dollars in thousands)
Mortgage backed securities (1)	$	66	$	3	$	—		$	69
States and political subdivisions		2,405		37		—			2,442
Other securities		500		—		—			500
Total	$	2,971	$	40	$	—		$	3,011
December 31, 2019
Mortgage backed securities (1)	$	93	$	4	$	—		$	97
States and political subdivisions		1,310		1		(5	)		1,306
Other securities		500		—		—			500
Total	$	1,903	$	5	$	(5	)	$	1,903

The following table summarizes the amortized cost and estimated fair values of debt securities available for sale:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
September 30, 2020	(Dollars in thousands)
U.S. treasuries	$	500,268	$	11,425	$	—		$	511,693
U.S. federal agencies		20,852		—		(63	)		20,789
Mortgage backed securities (1)		15,709		429		—			16,138
States and political subdivisions		32,157		479		—			32,636
Asset backed securities		13,333		—		(619	)		12,714
Total	$	582,319	$	12,333	$	(682	)	$	593,970
December 31, 2019
U.S. treasuries	$	409,488	$	4,974	$	(13	)	$	414,449
U.S. federal agencies		23,039		23		(38	)		23,024
Mortgage backed securities (1)		16,941		128		(64	)		17,005
States and political subdivisions		22,294		282		(45	)		22,531
Asset backed securities		13,320		—		(606	)		12,714
Total	$	485,082	$	5,407	$	(766	)	$	489,723

(1) Primarily consists of FHLMC, FNMA, GNMA and mortgage backed securities through U.S. agencies.

The maturities of debt securities held for investment and available for sale are summarized in the following table using contractual maturities. Actual maturities may differ from contractual maturities due to obligations that are called or prepaid. For purposes of the maturity table, mortgage-backed securities, which are not due at a single maturity date, have been presented at their contractual maturity.

	September 30, 2020				December 31, 2019
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(Dollars in thousands)
Held for Investment
Contractual maturity of debt securities:
Within one year	$	805	$	811	$	300	$	300
After one year but within five years		1,597		1,631		1,058		1,055
After five years but within ten years		568		568		543		546
After ten years		1		1		2		2
Total	$	2,971	$	3,011	$	1,903	$	1,903
Available for Sale
Contractual maturity of debt securities:
Within one year	$	331,600	$	332,496	$	186,373	$	186,539
After one year but within five years		209,080		219,983		252,519		257,430
After five years but within ten years		3,850		4,005		5,873		6,008
After ten years		37,789		37,486		40,317		39,746
Total debt securities	$	582,319	$	593,970	$	485,082	$	489,723

The following table is a summary of the Company’s book value of securities that were pledged as collateral for public funds on deposit, repurchase agreements and for other purposes as required or permitted by law:

	September 30, 2020		December 31, 2019
	(Dollars in thousands)
Book value of pledged securities	$	433,138	$	445,702