Investments (Tables)

9 Months Ended

Sep. 30, 2022

Investments, Debt and Equity Securities [Abstract]

Amortized Cost And Estimated Fair Value

The amortized cost, estimated fair value, and allowance for credit losses of available-for-sale and held-to-maturity investment securities are as follows:

Amortized Cost And Estimated Fair Value

(dollars in thousands, unaudited)

	September 30, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance for Credit Losses		Estimated Fair Value
Available-for-sale
U.S. government agencies	$	4,000	$	—	$	(45)	$	—	$	3,955
Mortgage-backed securities		202,882		—		(11,860)		—		191,022
State and political subdivisions		363,790		53		(43,114)		—		320,729
Corporate bonds		59,768		—		(5,432)		—		54,336
Collateralized loan obligations		514,701		119		(15,428)		—		499,392
Total available-for-sale securities	$	1,145,141	$	172	$	(75,879)	$	—	$	1,069,434
	Amortized Cost		Gross Unrecognized Gains		Gross Unrecognized Losses		Estimated Fair Value		Allowance for Credit Losses
Held-to-maturity
U.S. government agencies	$	6,113	$	—	$	(669)	$	5,444	$	—
Mortgage-backed securities		100,792		—		(9,941)		90,851		—
State and political subdivisions		49,324		11		(6,946)		42,389		(18)
Total held-to-maturity securities	$	156,229	$	11	$	(17,556)	$	138,684	$	(18)

	December 31, 2021
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance for Credit Losses		Estimated Fair Value
Available-for-sale
U.S. government agencies	$	1,546	$	28	$	—	$	—	$	1,574
Mortgage-backed securities		303,912		4,772		(1,957)		—		306,727
State and political subdivisions		290,729		13,807		(268)		—		304,268
Corporate bonds		28,436		94		(1)		—		28,529
Collateralized loan obligations		332,836		68		(688)		—		332,216
Total securities	$	957,459	$	18,769	$	(2,914)	$	—	$	973,314

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

The following table summarizes available-for-sale debt securities that were in an unrealized loss position for which an ACL has not been recorded, based on the length of time the individual securities have been in an unrealized loss position, including the number of available-for-sale debt securities in an unrealized loss position, as of the dates indicated below.

Investment Portfolio - Unrealized Losses

(dollars in thousands, unaudited)

		September 30, 2022
		Less than twelve months				Twelve months or more				Total
	Number of Securities	Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value
Available-for-sale
U.S. government agencies	2	$	(45)	$	3,955	$	—	$	—	$	(45)	$	3,955
Mortgage-backed securities	371		(11,696)		189,031		(164)		1,924		(11,860)		190,955
State and political subdivisions	399		(38,127)		286,459		(4,987)		13,878		(43,114)		300,337
Corporate bonds	51		(5,432)		54,336		—		—		(5,432)		54,336
Collateralized loan obligations	58		(15,200)		447,465		(228)		8,071		(15,428)		455,536
Total available-for-sale	881	$	(70,500)	$	981,246	$	(5,379)	$	23,873	$	(75,879)	$	1,005,119

		December 31, 2021
		Less than twelve months				Twelve months or more				Total
	Number of Securities	Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value
Available-for-sale
U.S. government agencies	—	$	—	$	—	$	—	$	—	$	—	$	—
Mortgage-backed securities	46		(1,797)		107,026		(160)		2,808		(1,957)		109,834
State and political subdivisions	29		(268)		30,170		—		—		(268)		30,170
Corporate bonds	1		(1)		499		—		—		(1)		499
Collateralized loan obligations	22		(688)		175,581		—		—		(688)		175,581
Total available-for-sale	98	$	(2,754)	$	313,276	$	(160)	$	2,808	$	(2,914)	$	316,084

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 September 30,					Nine months ended September 30,
	2022		2021		2022		2021
Proceeds from sales, calls and maturities of securities available for sale	$	3,540	$	1,948	$	34,071	$	5,948
Gross gains on sales, calls and maturities of securities available for sale		—		11		1,032		11
Gross losses on sales, calls and maturities of securities available for sale		—		—		—		—
Net gains on sale of securities available for sale	$	—	$	11	$	1,032	$	11

Investments Classified by Contractual Maturity Date

Estimated Fair Value of Contractual Maturities

(dollars in thousands, unaudited)

	September 30, 2022
	Available-for-Sale				Held-to-Maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Maturing within one year	$	908	$	908	$	675	$	667
Maturing after one year through five years		14,313		14,132		2,133		2,091
Maturing after five years through ten years		81,497		75,441		18,729		16,869
Maturing after ten years		330,840		288,539		33,900		28,207
Securities not due at a single maturity date:
Mortgage-backed securities		202,882		191,022		100,792		90,850
Collateralized loan obligations		514,701		499,392		—		—
	$	1,145,141	$	1,069,434	$	156,229	$	138,684

	December 31, 2021
	Available-for-Sale				Held-to-Maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Maturing within one year	$	3,513	$	3,547	$	—	$	—
Maturing after one year through five years		26,422		26,718		—		—
Maturing after five years through ten years		36,840		38,314		—		—
Maturing after ten years		253,936		265,792		—		—
Securities not due at a single maturity date:						—		—
Mortgage-backed securities		303,912		306,727		—		—
Collateralized loan obligations		332,836		332,216		—		—
	$	957,459	$	973,314	$	—	$	—

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)

	September 30, 2022				December 31, 2021
	Amortized		Fair Market		Amortized		Fair Market
General obligation bonds	Cost		Value		Cost		Value
State of issuance
Texas	$	159,391	$	139,498	$	85,045	$	89,225
California		67,310		58,161		64,092		67,066
Washington		22,417		20,670		23,858		24,812
Other (29 & 26 states, respectively)		107,784		95,355		75,037		78,579
Total general obligation bonds		356,902		313,684		248,032		259,682
Revenue bonds
State of issuance
Texas		9,496		8,460		7,038		7,377
California		3,994		3,613		1,349		1,392
Washington		4,093		3,387		4,334		4,602
Other (20 & 15 states, respectively)		38,629		33,974		29,976		31,215
Total revenue bonds		56,212		49,434		42,697		44,586
Total obligations of states and political subdivisions	$	413,114	$	363,118	$	290,729	$	304,268

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)

	September 30, 2022				December 31, 2021
	Amortized		Fair Market		Amortized		Fair Market
Revenue bonds	Cost		Value		Cost		Value
Revenue source:
Water	$	22,741	$	20,064	$	15,534	$	16,220
Lease		7,511		6,907		6,556		6,718
Sewer		7,091		6,144		3,932		4,165
Sales tax revenue		4,329		3,803		—		—
Intergovernmental agreement		2,836		2,600		—		—
Other (10 and 9 sources, respectively)		11,704		9,916		16,675		17,483
Total revenue bonds	$	56,212	$	49,434	$	42,697	$	44,586