Investments (Tables)

3 Months Ended

Mar. 31, 2020

Investments, Debt and Equity Securities [Abstract]

Amortized Cost and Estimated Fair Value of Available-For-Sale Investment Securities

The amortized cost and estimated fair value of available-for-sale investment securities are as follows:

Amortized Cost And Estimated Fair Value

(dollars in thousands, unaudited)

	March 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. government agencies	$	11,587	$	204	$	(49)	$	11,742
Mortgage-backed securities		393,680		11,742		(176)		405,246
State and political subdivisions		195,565		7,623		(22)		203,166
Total securities	$	600,832	$	19,569	$	(247)	$	620,154

	December 31, 2019
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. government agencies	$	12,125	$	124	$	(104)	$	12,145
Mortgage-backed securities		398,353		3,354		(1,318)		400,389
State and political subdivisions		181,900		6,478		(113)		188,265
Total securities	$	592,378	$	9,956	$	(1,535)	$	600,799

Realized Gain (Loss) on Investments

The table below summarizes the Company’s gross realized gains and losses as well as gross proceeds from the sales of securities, for the periods indicated:

Investment Portfolio - Realized Gains/(Losses)

(dollars in thousands, unaudited)

	Three months ended March 31,
	2020		2019
Proceeds from sales, calls and maturities of securities available for sale	$	2,430	$	16,654
Gross gains on sales, calls and maturities of securities available for sale		—		94
Gross losses on sales, calls and maturities of securities available for sale		—		(88)
Net gains on sale of securities available for sale	$	$—	$	$6

Information Pertaining to Investment Securities Aggregated by Investment Category and Length of Time that Individual Securities in a Continuous Loss Position

Gross unrealized losses on our investment securities as of the indicated dates are disclosed in the table below, categorized by investment type and by the duration of time that loss positions on individual securities have continuously existed (over or under twelve months).

Investment Portfolio - Unrealized Losses

(dollars in thousands, unaudited)

	March 31, 2020
	Less than twelve months				Twelve months or more
	Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value
U.S. government agencies	$	(3)	$	1,199	$	(46)	$	2,587
Mortgage-backed securities		(94)		7,717		(82)		8,717
State and political subdivisions		(22)		5,791		—		—
Total	$	(119)	$	14,707	$	(128)	$	11,304

	December 31, 2019
	Less than twelve months				Twelve months or more
	Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value
U.S. government agencies	$	(32)	$	3,240	$	(72)	$	2,689
Mortgage-backed securities		(494)		100,518		(824)		78,538
State and political subdivisions		(113)		19,762		—		—
Total	$	(639)	$	123,520	$	(896)	$	81,227

Investments Classified by Contractual Maturity Date

	Three months ended March 31,
	2020		2019
Proceeds from sales, calls and maturities of securities available for sale	$	2,430	$	16,654
Gross gains on sales, calls and maturities of securities available for sale		—		94
Gross losses on sales, calls and maturities of securities available for sale		—		(88)
Net gains on sale of securities available for sale	$	$—	$	$6

The amortized cost and estimated fair value of investment securities available-for-sale at March 31, 2020 and December 31, 2019 are shown below, grouped by the remaining time to contractual maturity dates.  The expected life of investment securities may not be consistent with contractual maturity dates, since the issuers of the securities might have the right to call or prepay obligations with or without penalties.

Estimated Fair Value of Contractual Maturities

(dollars in thousands, unaudited)

	March 31, 2020
	Amortized Cost		Fair Value
Maturing within one year	$	7,037	$	7,158
Maturing after one year through five years		15,424		15,631
Maturing after five years through ten years		35,850		36,927
Maturing after ten years		148,842		155,192
Securities not due at a single maturity date:
Mortgage-backed securities		194,774		199,613
Collateralized mortgage obligations		198,905		205,633
	$	600,832	$	620,154

	December 31, 2019
	Amortized Cost		Fair Value
Maturing within one year	$	7,155	$	7,244
Maturing after one year through five years		17,008		17,171
Maturing after five years through ten years		33,805		34,881
Maturing after ten years		136,057		141,114
Securities not due at a single maturity date:
Mortgage-backed securities		189,554		190,488
Collateralized mortgage obligations		208,799		209,901
	$	592,378	$	600,799

Summary of Amortized Cost and Fair Values of General Obligation and Revenue Bonds

The following table summarizes the amortized cost and fair values of general obligation and revenue bonds in the Company’s investment securities portfolio at the indicated dates, identifying the state in which the issuing municipality or agency operates for our largest geographic concentrations:

Revenue and General Obligation Bonds by Location

(dollars in thousands, unaudited)

	March 31, 2020				December 31, 2019
	Amortized		Fair Market		Amortized		Fair Market
General obligation bonds	Cost		Value		Cost		Value
State of issuance
Texas	$	65,619	$	68,182	$	59,439	$	61,519
Washington		23,445		24,579		23,392		24,313
California		23,873		24,996		23,882		25,030
Other (24 states)		54,712		56,580		49,326		50,725
Total general obligation bonds		167,649		174,337		156,039		161,587
Revenue bonds
State of issuance
Texas		7,068		7,320		6,035		6,298
Washington		2,787		2,927		1,737		1,856
California		364		379		365		380
Other (13 states)		17,697		18,203		17,724		18,144
Total revenue bonds		27,916		28,829		25,861		26,678
Total obligations of states and political subdivisions	$	195,565	$	203,166	$	181,900	$	188,265

The revenue bonds in the Company’s investment securities portfolios were issued by government municipalities and agencies to fund public services such as utilities (water, sewer, and power), educational facilities, and general public and economic improvements.  The primary sources of revenue for these bonds are delineated in the table below, which shows the amortized cost and fair market values for the largest revenue concentrations as of the indicated dates.

Revenue Bonds by Type

(dollars in thousands, unaudited)

	March 31, 2020				December 31, 2019
	Amortized		Fair Market		Amortized		Fair Market
Revenue bonds	Cost		Value		Cost		Value
Revenue source:
Water	$	7,499	$	7,774	$	7,515	$	7,775
Sewer		4,752		4,854		4,760		4,811
Lease		4,639		4,751		3,596		3,678
College & university		1,993		2,031		1,997		2,019
Sales tax		1,945		1,988		1,949		1,995
Electric & power		1,419		1,478		1,421		1,521
Other (8 and 7 sources, respectively)		5,669		5,953		4,623		4,879
Total revenue bonds	$	27,916	$	28,829	$	25,861	$	26,678