INVESTMENT SECURITIES (Tables)

6 Months Ended

Jun. 30, 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   June 30, 2021 and December 31, 2020 are as follows:

	June 30, 2021								December 31, 2020
			Gross		Gross						Gross		Gross
	Amortized		Unrealized		Unrealized		Fair		Amortized		Unrealized		Unrealized		Fair
(000's omitted)	Cost		Gains		Losses		Value		Cost		Gains		Losses		Value
Available-for-Sale Portfolio:
U.S. Treasury and agency securities	$	3,082,187	$	52,960	$	110,075	$	3,025,072	$	2,423,236	$	94,741	$	16,595	$	2,501,382
Obligations of state and political subdivisions		405,245		20,908		1		426,152		451,028		24,632		0		475,660
Government agency mortgage-backed securities		521,056		10,999		2,916		529,139		506,540		16,280		182		522,638
Corporate debt securities		3,000		94		0		3,094		4,499		137		1		4,635
Government agency collateralized mortgage obligations		28,490		796		4		29,282		42,476		1,111		10		43,577
Total available-for-sale portfolio	$	4,039,978	$	85,757	$	112,996	$	4,012,739	$	3,427,779	$	136,901	$	16,788	$	3,547,892
Equity and other Securities:
Equity securities, at fair value	$	251	$	218	$	0	$	469	$	251	$	194	$	0	$	445
Federal Home Loan Bank common stock		7,262		0		0		7,262		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		2,526		750		0		3,276		4,876		750		0		5,626
Total equity and other securities	$	43,955	$	968	$	0	$	44,923	$	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 is as follows:

As of June 30, 2021

	Less than 12 Months					12 Months or Longer					Total
				Gross					Gross					Gross
		Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
(000's omitted)	#	Value		Losses		#	Value		Losses		#	Value		Losses
Available-for-Sale Portfolio:
U.S. Treasury and agency securities	29	$	1,272,423	$	110,075	0	$	0	$	0	29	$	1,272,423	$	110,075
Obligations of state and political subdivisions	4		1,651		1	0		0		0	4		1,651		1
Government agency mortgage-backed securities	126		170,661		2,914	6		1,146		2	132		171,807		2,916
Government agency collateralized mortgage obligations	3		1,804		3	3		182		1	6		1,986		4
Total available-for-sale investment portfolio	162	$	1,446,539	$	112,993	9	$	1,328	$	3	171	$	1,447,867	$	112,996

As of December 31, 2020

	Less than 12 Months					12 Months or Longer					Total
				Gross					Gross					Gross
		Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
(000's omitted)	#	Value		Losses		#	Value		Losses		#	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 June 30, 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		Fair
(000's omitted)	Cost		Value
Due in one year or less	$	198,566	$	199,557
Due after one through five years		768,349		796,228
Due after five years through ten years		1,018,820		1,037,749
Due after ten years		1,504,697		1,420,784
Subtotal		3,490,432		3,454,318
Government agency mortgage-backed securities		521,056		529,139
Government agency collateralized mortgage obligations		28,490		29,282
Total	$	4,039,978	$	4,012,739