XML 34 R25.htm IDEA: XBRL DOCUMENT v3.23.1
INVESTMENT SECURITIES (Tables)
 3 Months Ended
Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]  
Summary of Amortized Cost, Gross Unrealized Gains and Losses, Gross Unrealized Losses and Approximate Fair Value of Investment Securities
The following table summarizes the amortized cost, gross unrealized gains and losses and approximate fair value of investment securities available for sale as of March 31, 2023 and December 31, 2022.

 Amortized
Cost		Gross Unrealized
Gains		Gross Unrealized
Losses		Fair
Value
Available for sale at March 31, 2023    
U.S. Treasury$2,114 $— $32 $2,082 
U.S. Government-sponsored agency securities117,746 5 15,153 102,598 
State and municipal1,322,500 562 139,326 1,183,736 
U.S. Government-sponsored mortgage-backed securities584,576 — 90,971 493,605 
Corporate obligations12,991 — 804 12,187 
Total available for sale$2,039,927 $567 $246,286 $1,794,208 

 Amortized
Cost		Gross Unrealized
Gains		Gross Unrealized
Losses		Fair
Value
Available for sale at December 31, 2022    
U.S. Treasury$2,501 $— $42 $2,459 
U.S. Government-sponsored agency securities119,154 — 17,192 101,962 
State and municipal1,530,048 438 178,726 1,351,760 
U.S. Government-sponsored mortgage-backed securities608,630 1 100,358 508,273 
Corporate obligations13,014 — 807 12,207 
Total available for sale$2,273,347 $439 $297,125 $1,976,661 




The following table summarizes the amortized cost, gross unrealized gains and losses, approximate fair value and allowance for credit losses on investment securities held to maturity as of March 31, 2023 and December 31, 2022.

Amortized
Cost		Allowance for Credit LossesNet Carrying AmountGross Unrealized
Gains		Gross Unrealized
Losses		Fair
Value
Held to maturity at March 31, 2023   
U.S. Government-sponsored agency securities$388,273 $— $388,273 $— $61,813 $326,460 
State and municipal1,114,874 245 1,114,629 1,778 166,679 949,973 
U.S. Government-sponsored mortgage-backed securities758,779 — 758,779 — 102,068 656,711 
Foreign investment1,500 — 1,500 — 43 1,457 
Total held to maturity$2,263,426 $245 $2,263,181 $1,778 $330,603 $1,934,601 


Amortized
Cost		Allowance for Credit LossesNet Carrying AmountGross Unrealized
Gains		Gross Unrealized
Losses		Fair
Value
Held to maturity at December 31, 2022    
U.S. Government-sponsored agency securities$392,246 $— $392,246 $— $69,147 $323,099 
State and municipal1,117,552 245 1,117,307 647 197,064 921,135 
U.S. Government-sponsored mortgage-backed securities776,074 — 776,074 — 113,915 662,159 
Foreign investment1,500 — 1,500 — 28 1,472 
Total held to maturity$2,287,372 $245 $2,287,127 $647 $380,154 $1,907,865 
Summary of Amortized Cost of Investment Securities Held to Maturity Aggregated by Credit Quality Indicator
On a quarterly basis, the Corporation monitors the credit quality of investment securities held to maturity through the use of credit ratings. The following table summarizes the amortized cost of investment securities held to maturity at March 31, 2023, aggregated by credit quality indicator.
Held to Maturity
State and municipalOtherTotal
Credit Rating:
Aaa$108,774 $70,583 $179,357 
Aa1156,209 — 156,209 
Aa2183,736 — 183,736 
Aa3135,167 — 135,167 
A1131,421 — 131,421 
A210,170 — 10,170 
A310,120 — 10,120 
Non-rated379,277 1,077,969 1,457,246 
Total$1,114,874 $1,148,552 $2,263,426 
Summary of Investment Securities in a Continuous Unrealized Loss Position
The following tables summarize, as of March 31, 2023 and December 31, 2022, investment securities available for sale in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by security type and length of time in a continuous unrealized loss position.
Less than 12 Months12 Months or LongerTotal
Fair
Value		Gross
Unrealized
Losses		Fair
Value		Gross
Unrealized
Losses		Fair
Value		Gross
Unrealized
Losses
Investment securities available for sale at March 31, 2023
U.S. Treasury$737 $8 $957 $24 $1,694 $32 
U.S. Government-sponsored agency securities36,595 2,204 65,197 12,949 101,792 15,153 
State and municipal290,254 13,634 823,441 125,692 1,113,695 139,326 
U.S. Government-sponsored mortgage-backed securities54,013 2,801 439,588 88,170 493,601 90,971 
Corporate obligations11,253 708 904 96 12,157 804 
Total investment securities available for sale$392,852 $19,355 $1,330,087 $226,931 $1,722,939 $246,286 

 
Less than 12 Months12 Months or LongerTotal
Fair
Value		Gross
Unrealized
Losses		Fair
Value		Gross
Unrealized
Losses		Fair
Value		Gross
Unrealized
Losses
Investment securities available for sale at December 31, 2022
U.S. Treasury$2,459 $42 $— $— $2,459 $42 
U.S. Government-sponsored agency securities48,940 4,973 53,022 12,219 101,962 17,192 
State and municipal1,177,104 150,096 108,652 28,630 1,285,756 178,726 
U.S. Government-sponsored mortgage-backed securities182,700 16,910 325,455 83,448 508,155 100,358 
Corporate obligations12,176 807 — — 12,176 807 
Total investment securities available for sale$1,423,379 $172,828 $487,129 $124,297 $1,910,508 $297,125 


The following table summarizes investment securities available for sale in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by security type and the number of securities in the portfolio for the periods indicated.

Gross
Unrealized
Losses		Number of Securities
Investment securities available for sale at March 31, 2023
U.S. Treasury$32 3
U.S. Government-sponsored agency securities15,153 15
State and municipal139,326 765
U.S. Government-sponsored mortgage-backed securities90,971 173
Corporate obligations804 10
Total investment securities available for sale$246,286 966 

Gross
Unrealized
Losses		Number of Securities
Investment securities available for sale at December 31, 2022
U.S. Treasury$42 5
U.S. Government-sponsored agency securities17,192 16
State and municipal178,726 946
U.S. Government-sponsored mortgage-backed securities100,358 177
Corporate obligations807 10
Total investment securities available for sale$297,125 1,154 
Summary of Investments in Debt and Equity Securities Reported in the Financial Statements at an Amount Less Than Their Historical Cost
Certain investment securities available for sale are reported in the financial statements at an amount less than their historical cost as indicated in the table below.
March 31, 2023December 31, 2022
Investments available for sale reported at less than historical cost:  
Historical cost$1,969,225 $2,207,633 
Fair value1,722,939 1,910,508 
Gross unrealized losses$246,286 $297,125 
Percent of the Corporation's investments available for sale96.0 %96.7 %
Summary of Amortized Cost and Fair Value of Available for Sale Securities and Held to Maturity Securities by Contractual Maturity
The amortized cost and fair value of investment securities available for sale and held to maturity at March 31, 2023 and December 31, 2022, by contractual maturity are shown below. Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity are shown separately.
 Available for SaleHeld to Maturity
 Amortized CostFair ValueAmortized CostFair Value
Maturity Distribution at March 31, 2023    
Due in one year or less$1,861 $1,854 $12,168 $12,225 
Due after one through five years21,853 20,346 112,941 105,185 
Due after five through ten years118,743 113,564 120,969 114,725 
Due after ten years1,312,894 1,164,839 1,258,569 1,045,755 
 1,455,351 1,300,603 1,504,647 1,277,890 
U.S. Government-sponsored mortgage-backed securities584,576 493,605 758,779 656,711 
Total investment securities$2,039,927 $1,794,208 $2,263,426 $1,934,601 

Available for SaleHeld to Maturity
Amortized CostFair ValueAmortized CostFair Value
Maturity Distribution at December 31, 2022    
Due in one year or less$2,822 $2,809 $13,697 $13,749 
Due after one through five years11,694 11,265 80,697 76,453 
Due after five through ten years169,729 161,211 147,078 135,027 
Due after ten years1,480,472 1,293,103 1,269,826 1,020,477 
 1,664,717 1,468,388 1,511,298 1,245,706 
U.S. Government-sponsored mortgage-backed securities608,630 508,273 776,074 662,159 
Total investment securities$2,273,347 $1,976,661 $2,287,372 $1,907,865 
Summary of Gross Gains and Losses on Sales and Redemptions of Available for Sale Securities
Gross gains and losses on the sales and redemptions of investment securities available for sale for the three months ended March 31, 2023 and 2022 are shown below.
Three Months Ended
March 31,
20232022
Sales and redemptions of investment securities available for sale:  
Gross gains$12 $578 
Gross losses(1,583)(12)
Net gains (losses) on sales and redemptions of investment securities available for sale$(1,571)$566