Investment Securities (Tables)

3 Months Ended

Mar. 31, 2023

Summary of Amortized Cost, Estimated Fair Values and Allowance for Credit Losses of Available for Sale Securities

The amortized cost, estimated fair values, and allowance for credit losses of securities available for sale are summarized as follows.

	March 31, 2023
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance For Credit Losses		Estimated Fair Value
U.S. Treasury securities and obligations of U.S. Government corporations and agencies	$	546,302	$	7	$	15,139	$	0	$	531,170
State and political subdivisions		812,022		84		90,132		0		721,974
Residential mortgage-backed securities
Agency		1,339,271		48		173,664		0		1,165,655
Non-agency		121,001		114		10,364		0		110,751
Commercial mortgage-backed securities
Agency		594,150		9		57,149		0		537,010
Asset-backed securities		922,890		0		25,763		0		897,127
Single issue trust preferred securities		17,352		0		1,514		0		15,838
Other corporate securities		477,355		0		37,467		0		439,888
Total	$	4,830,343	$	262	$	411,192	$	0	$	4,419,413

	December 31, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance For Credit Losses		Estimated Fair Value
U.S. Treasury securities and obligations of U.S. Government corporations and agencies	$	548,407	$	12	$	18,927	$	0	$	529,492
State and political subdivisions		820,167		36		110,673		0		709,530
Residential mortgage-backed securities
Agency		1,369,471		4		194,531		0		1,174,944
Non-agency		121,336		66		9,429		0		111,973
Commercial mortgage-backed securities
Agency		627,768		8		65,223		0		562,553
Asset-backed securities		943,813		0		32,202		0		911,611
Single issue trust preferred securities		17,342		88		1,146		0		16,284
Other corporate securities		563,425		44		37,931		0		525,538
Total	$	5,011,729	$	258	$	470,062	$	0	$	4,541,925

Summary of Securities Available for Sale in an Unrealized Loss Position

The following is a summary of securities available for sale which were in an unrealized loss position at March 31, 2023 and December 31, 2022.

	Less than 12 months				12 months or longer				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
March 31, 2023
U.S. Treasury securities and obligations of U.S. Government corporations and agencies	$	180,725	$	2,531	$	343,241	$	12,608	$	523,966	$	15,139
State and political subdivisions		69,465		1,481		623,467		88,651		692,932		90,132
Residential mortgage-backed securities
Agency		122,666		4,408		1,033,590		169,256		1,156,256		173,664
Non-agency		35,839		1,434		64,619		8,930		100,458		10,364
Commercial mortgage-backed securities
Agency		160,615		3,359		373,494		53,790		534,109		57,149
Asset-backed securities		145,986		2,368		751,141		23,395		897,127		25,763
Single issue trust preferred securities		3,054		36		12,784		1,478		15,838		1,514
Other corporate securities		92,339		5,552		334,813		31,915		427,152		37,467
Total	$	810,689	$	21,169	$	3,537,149	$	390,023	$	4,347,838	$	411,192

	Less than 12 months				12 months or longer				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
December 31, 2022
U.S. Treasury securities and obligations of U.S. Government corporations and agencies	$	473,025	$	13,628	$	48,793	$	5,299	$	521,818	$	18,927
State and political subdivisions		496,328		63,019		192,234		47,654		688,562		110,673
Residential mortgage-backed securities
Agency		623,587		70,744		550,135		123,787		1,173,722		194,531
Non-agency		58,839		2,083		42,901		7,346		101,740		9,429
Commercial mortgage-backed securities
Agency		396,380		27,469		163,226		37,754		559,606		65,223
Asset-backed securities		425,482		14,134		486,129		18,068		911,611		32,202
Single issue trust preferred securities		0		0		13,109		1,146		13,109		1,146
Other corporate securities		195,425		18,064		261,170		19,867		456,595		37,931
Total	$	2,669,066	$	209,141	$	1,757,697	$	260,921	$	4,426,763	$	470,062

Summary of Gains or Losses on Proceeds from Maturities, Sales and Calls of Available for Sale Securities by Specific Identification Method

	Three Months Ended March 31
	2023		2022
Proceeds from maturities, sales and calls	$	185,748	$	151,627
Gross realized gains		0		0
Gross realized losses		420		0

Summary of Maturities of Debt Securities Held to Maturity by Amortized Cost and Estimated Fair Value

	March 31, 2023				December 31, 2022
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due in one year or less	$	593,961	$	583,284	$	384,921	$	380,575
Due after one year through five years		556,379		528,037		856,743		817,881
Due after five years through ten years		960,695		852,251		981,983		858,819
Due after ten years		2,719,308		2,455,841		2,788,082		2,484,650
Total	$	4,830,343	$	4,419,413	$	5,011,729	$	4,541,925

Summary of Equity Securities

Equity securities consist mainly of mutual funds of equity securities within a rabbi trust for the payment of benefits under a deferred compensation plan for certain key officers of United and its subsidiaries. The fair value of United’s equity securities was $7,792 at March 31, 2023 and $7,629 at December 31, 2022.

	Three Months Ended March 31
	2023			2022
Net gains recognized during the period on equity securities sold	$	0		$	0
Unrealized gains recognized during the period on equity securities still held at period end		82			19
Unrealized losses recognized during the period on equity securities still held at period end		(67	)		(270	)
Net gains (losses) recognized during the period	$	15		$	(251	)