Securities (Tables)
 6 Months Ended
Jun. 30, 2023
Investments, Debt and Equity Securities [Abstract]  
Schedule of available-for-sale securities
The following tables summarize available-for-sale debt securities held by the Company at June 30, 2023 and December 31, 2022:
Available-for-Sale Debt Securities
June 30, 2023Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Fair Value
(In thousands)
U.S. Treasuries$190,275 $0 $22,181 $168,094 
Obligations of U.S. Government sponsored entities592,694 0 69,151 523,543 
Obligations of U.S. states and political subdivisions90,330 1 8,284 82,047 
Mortgage-backed securities – residential, issued by
 U.S. Government agencies54,852 9 5,919 48,942 
 U.S. Government sponsored entities757,400 0 114,265 643,135 
U.S. corporate debt securities2,500 0 258 2,242 
Total available-for-sale debt securities$1,688,051 $10 $220,058 $1,468,003 
 
Available-for-Sale Debt Securities
December 31, 2022Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Fair Value
(In thousands)
U.S. Treasuries$190,170 $0 $22,919 $167,251 
Obligations of U.S. Government sponsored entities681,192 0 80,025 601,167 
Obligations of U.S. states and political subdivisions93,599 8 8,326 85,281 
Mortgage-backed securities – residential, issued by
U.S. Government agencies58,727 12 6,071 52,668 
U.S. Government sponsored entities805,603 0 119,381 686,222 
U.S. corporate debt securities2,500 0 122 2,378 
Total available-for-sale debt securities$1,831,791 $20 $236,844 $1,594,967 
Schedule of held-to-maturity securities
The following tables summarize held-to-maturity debt securities held by the Company at June 30, 2023 and December 31, 2022:

Held-to-Maturity Securities
June 30, 2023Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Fair Value
(In thousands)
U.S. Treasuries$86,370 $0 $12,598 $73,772 
Obligations of U.S. Government sponsored entities225,999 0 37,327 188,672 
Total held-to-maturity debt securities$312,369 $0 $49,925 $262,444 

Held-to-Maturity Securities
December 31, 2022Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Fair Value
(In thousands)
U.S. Treasuries$86,478 $0 $12,937 $73,541 
Obligations of U.S. Government sponsored entities225,866 0 37,715 188,151 
Total held-to-maturity debt securities$312,344 $0 $50,652 $261,692 
The following table summarizes held-to-maturity debt securities that had unrealized losses at June 30, 2023 and December 31, 2022:

June 30, 2023Less than 12 Months12 Months or LongerTotal
(In thousands)Fair ValueUnrealized LossesFair ValueUnrealized LossesFair ValueUnrealized Losses
U.S. Treasuries$0 $0 $73,772 $12,598 $73,772 $12,598 
Obligations of U.S. Government sponsored entities8,176 751 180,496 36,576 188,672 37,327 
Total held-to-maturity debt securities$8,176 $751 $254,268 $49,174 $262,444 $49,925 

December 31, 2022Less than 12 Months12 Months or LongerTotal
(In thousands)Fair ValueUnrealized LossesFair ValueUnrealized LossesFair ValueUnrealized Losses
U.S. Treasuries$0 $0 $73,542 $12,937 $73,542 $12,937 
Obligations of U.S. Government sponsored entities24,543 3,903 163,607 33,812 188,150 37,715 
Total held-to-maturity debt securities$24,543 $3,903 $237,149 $46,749 $261,692 $50,652 
Schedule of available-for-sale securities with unrealized losses
The following table summarizes available-for-sale debt securities that had unrealized losses at June 30, 2023, and December 31, 2022:

June 30, 2023Less than 12 Months12 Months or LongerTotal
(In thousands)Fair ValueUnrealized LossesFair ValueUnrealized LossesFair ValueUnrealized Losses
U.S. Treasuries$0 $0 $168,094 $22,181 $168,094 $22,181 
Obligations of U.S. Government sponsored entities28,596 758 494,947 68,393 523,543 69,151 
Obligations of U.S. states and political subdivisions26,104 756 55,842 7,528 81,946 8,284 
Mortgage-backed securities – residential, issued by
U.S. Government agencies6,244 254 42,351 5,665 48,595 5,919 
U.S. Government sponsored entities13,055 727 630,081 113,538 643,136 114,265 
U.S. corporate debt securities0 0 2,242 258 2,242 258 
Total available-for-sale debt securities$73,999 $2,495 $1,393,557 $217,563 $1,467,556 $220,058 
December 31, 2022Less than 12 Months12 Months or LongerTotal
(In thousands)Fair ValueUnrealized LossesFair ValueUnrealized LossesFair ValueUnrealized Losses
U.S. Treasuries$28,602 $2,132 $138,649 $20,787 $167,251 $22,919 
Obligations of U.S. Government sponsored entities143,794 7,508 457,373 72,517 601,167 80,025 
Obligations of U.S. states and political subdivisions46,638 2,385 33,435 5,941 80,073 8,326 
Mortgage-backed securities – residential, issued by
U.S. Government agencies22,9451,25829,3564,81352,3016,071
U.S. Government sponsored entities186,69016,869499,532102,512686,222119,381
U.S. corporate debt securities0 0 2,378 122 2,378 122 
Total available-for-sale debt securities$428,669 $30,152 $1,160,723 $206,692 $1,589,392 $236,844 
Schedule of amortized cost and estimated fair value of debt securities by contractual maturity
June 30, 2023
(In thousands)Amortized CostFair Value
Available-for-sale debt securities:
Due in one year or less$47,677 $46,893 
Due after one year through five years514,770 461,320 
Due after five years through ten years269,157 230,292 
Due after ten years44,195 37,421 
Total875,799 775,926 
Mortgage-backed securities812,252 692,077 
Total available-for-sale debt securities$1,688,051 $1,468,003 

December 31, 2022
(In thousands)Amortized CostFair Value
Available-for-sale debt securities:
Due in one year or less$50,922 $50,269 
Due after one year through five years508,880 459,721 
Due after five years through ten years367,743 314,408 
Due after ten years39,916 31,679 
Total967,461 856,077 
Mortgage-backed securities864,330 738,890 
Total available-for-sale debt securities$1,831,791 $1,594,967 
June 30, 2023
(In thousands)Amortized CostFair Value
Held-to-maturity debt securities:
Due after five years through ten years$312,369 $262,444 
Total held-to-maturity debt securities$312,369 $262,444 

December 31, 2022
(In thousands)Amortized CostFair Value
Held-to-maturity debt securities:
Due after five years through ten years$312,344 $261,692 
Total held-to-maturity debt securities$312,344 $261,692