INVESTMENT SECURITIES (Tables)

12 Months Ended

Dec. 31, 2021

INVESTMENT SECURITIES.

Schedule of amortized cost and estimated fair value of investment securities

The amortized cost and estimated fair value of investment securities as of December 31 are as follows:

	2021								2020
			Gross		Gross						Gross		Gross
	Amortized		Unrealized		Unrealized		Estimated		Amortized		Unrealized		Unrealized		Estimated
(000’s omitted)	Cost		Gains		Losses		Fair Value		Cost		Gains		Losses		Fair Value
Available-for-Sale Portfolio:
U.S. Treasury and agency securities	$	4,064,624	$	39,997	$	106,057	$	3,998,564	$	2,423,236	$	94,741	$	16,595	$	2,501,382
Obligations of state and political subdivisions		413,019		17,326		56		430,289		451,028		24,632		0		475,660
Government agency mortgage-backed securities		474,506		7,615		5,065		477,056		506,540		16,280		182		522,638
Corporate debt securities		8,000		39		77		7,962		4,499		137		1		4,635
Government agency collateralized mortgage obligations		19,953		410		24		20,339		42,476		1,111		10		43,577
Total available-for-sale portfolio	$	4,980,102	$	65,387	$	111,279	$	4,934,210	$	3,427,779	$	136,901	$	16,788	$	3,547,892
Equity and other Securities:
Equity securities, at fair value	$	251	$	212	$	0	$	463	$	251	$	194	$	0	$	445
Federal Home Loan Bank common stock		7,188		0		0		7,188		7,468		0		0		7,468
Federal Reserve Bank common stock		33,916		0		0		33,916		33,916		0		0		33,916
Other equity securities, at adjusted cost		2,562		750		0		3,312		4,876		750		0		5,626
Total equity and other securities	$	43,917	$	962	$	0	$	44,879	$	46,511	$	944	$	0	$	47,455

Schedule of investment securities that have been in a continuous unrealized loss position for less than or greater than twelve months

A summary of investment securities that have been in a continuous unrealized loss position for less than or greater than twelve months is as follows:

As of December 31, 2021

	Less than 12 Months					12 Months or Longer					Total
				Gross					Gross					Gross
				Unrealized					Unrealized					Unrealized
(000’s omitted)	#	Fair Value		Losses		#	Fair Value		Losses		#	Fair Value		Losses
Available-for-Sale Portfolio:
U.S. Treasury and agency securities	47	$	1,224,101	$	14,873	13	$	900,462	$	91,184	60	$	2,124,563	$	106,057
Obligations of state and political subdivisions	27		23,966		56	0		0		0	27		23,966		56
Government agency mortgage-backed securities	147		139,442		2,475	52		67,273		2,590	199		206,715		5,065
Corporate debt securities	1		4,923		77	0		0		0	1		4,923		77
Government agency collateralized mortgage obligations	18		3,146		24	1		53		0	19		3,199		24
Total available-for-sale investment portfolio	240	$	1,395,578	$	17,505	66	$	967,788	$	93,774	306	$	2,363,366	$	111,279

As of December 31, 2020

	Less than 12 Months					12 Months or Longer					Total
				Gross					Gross					Gross
				Unrealized					Unrealized					Unrealized
(000’s omitted)	#	Fair Value		Losses		#	Fair Value		Losses		#	Fair Value		Losses
Available-for-Sale Portfolio:
U.S. Treasury and agency securities	13	$	831,015	$	16,595	0	$	0	$	0	13	$	831,015	$	16,595
Obligations of state and political subdivisions	1		358		0	0		0		0	1		358		0
Government agency mortgage-backed securities	89		75,992		182	2		14		0	91		76,006		182
Corporate debt securities	1		1,001		1	0		0		0	1		1,001		1
Government agency collateralized mortgage obligations	13		5,246		10	1		0		0	14		5,246		10
Total available-for-sale investment portfolio	117	$	913,612	$	16,788	3	$	14	$	0	120	$	913,626	$	16,788

Schedule of amortized cost and estimated fair value of debt securities by contractual maturity

The amortized cost and estimated fair value of debt securities at December 31, 2021, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because borrowers may 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.

	Available-for-Sale
	Amortized
(000’s omitted)	Cost		Fair Value
Due in one year or less	$	156,262	$	158,119
Due after one through five years		876,849		891,772
Due after five years through ten years		1,958,202		1,962,453
Due after ten years		1,494,330		1,424,471
Subtotal		4,485,643		4,436,815
Government agency mortgage-backed securities		474,506		477,056
Government agency collateralized mortgage obligations		19,953		20,339
Total	$	4,980,102	$	4,934,210