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Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | $ 1,551,042 | $ 1,566,779
Available for Sale, Fair Value |  |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,405,602 | 1,399,154
Held to Maturity, Fair Value |  |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 1,678,376 | 1,705,120
Held to Maturity, Fair Value, Total | 1,519,504 | 1,524,710
Available for Sale Securities and Held to Maturity Securities Amortized Cost | 3,229,418 |
Debt Securities, Available-for-sale and Held-to-maturity | 2,925,106 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost | 107,197 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value | 104,149 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost | 1,280,338 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value | 1,179,694 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost | 787,194 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value | 696,863 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Amortized Cost | 1,054,689 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Fair Value | 944,400 |
U.S. government agency securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 0 |
Available for Sale, Amortized Cost, Due after one year to five years | 117,578 |
Available for Sale, Amortized Cost, Due after five to ten years | 113,175 |
Available for Sale, Amortized Cost, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 230,753 | 230,936
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 0 |
Available for Sale, Fair Value, Due after one year to five years | 106,039 |
Available for Sale, Fair Value, Due after five to ten years | 98,975 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 205,014 | 202,300
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 0 |
Held to Maturity, Amortized Cost, Due after one year to five years | 30,824 |
Held to Maturity, Amortized Cost, Due after five to ten years | 0 |
Held to Maturity, Amortized Cost, Due after ten years | 0 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 0 |
Held to Maturity, Fair Value, Due after one year to five years | 28,958 |
Held to Maturity, Fair Value, Due after five to ten years | 0 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 30,824 | 31,258
Held to Maturity, Fair Value, Total | 28,958 | 29,036
Small Business Administration Pooled Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 0 |
Available for Sale, Amortized Cost, Due after one year to five years | 0 |
Available for Sale, Amortized Cost, Due after five to ten years | 0 |
Available for Sale, Amortized Cost, Due after ten years | 57,648 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 57,648 | 59,470
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 0 |
Available for Sale, Fair Value, Due after one year to five years | 0 |
Available for Sale, Fair Value, Due after five to ten years | 0 |
Available for Sale, Fair Value, Due after ten years | 50,753 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 50,753 | 51,757
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 0 |
Held to Maturity, Amortized Cost, Due after one year to five years | 0 |
Held to Maturity, Amortized Cost, Due after five to ten years | 3,389 |
Held to Maturity, Amortized Cost, Due after ten years | 132,394 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 0 |
Held to Maturity, Fair Value, Due after one year to five years | 0 |
Held to Maturity, Fair Value, Due after five to ten years | 3,132 |
Held to Maturity, Fair Value, Due after ten years | 129,210 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 135,783 | 136,830
Held to Maturity, Fair Value, Total | 132,342 | 130,918
Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 107,116 |
Available for Sale, Amortized Cost, Due after one year to five years | 905,098 |
Available for Sale, Amortized Cost, Due after five to ten years | 295,745 |
Available for Sale, Amortized Cost, Due after ten years | 243,083 |
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 104,069 |
Available for Sale, Fair Value, Due after one year to five years | 827,738 |
Available for Sale, Fair Value, Due after five to ten years | 258,591 |
Available for Sale, Fair Value, Due after ten years | 215,204 |
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 81 |
Held to Maturity, Amortized Cost, Due after one year to five years | 375,240 |
Held to Maturity, Amortized Cost, Due after five to ten years | 491,449 |
Held to Maturity, Amortized Cost, Due after ten years | 811,606 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 80 |
Held to Maturity, Fair Value, Due after one year to five years | 351,956 |
Held to Maturity, Fair Value, Due after five to ten years | 438,272 |
Held to Maturity, Fair Value, Due after ten years | 729,196 |
Held to Maturity, Fair Value, Total | 1,519,504 |
Pooled trust preferred securities issued by banks and insurers |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 0 |
Available for Sale, Amortized Cost, Due after one year to five years | 0 |
Available for Sale, Amortized Cost, Due after five to ten years | 0 |
Available for Sale, Amortized Cost, Due after ten years | 1,203 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 1,203 | 1,203
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 0 |
Available for Sale, Fair Value, Due after one year to five years | 0 |
Available for Sale, Fair Value, Due after five to ten years | 0 |
Available for Sale, Fair Value, Due after ten years | 1,042 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,042 | 1,034
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [Member] |  |
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 0 |
Held to Maturity, Amortized Cost, Due after one year to five years | 0 |
Held to Maturity, Amortized Cost, Due after five to ten years | 1,500 |
Held to Maturity, Amortized Cost, Due after ten years | 0 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 0 |
Held to Maturity, Fair Value, Due after one year to five years | 0 |
Held to Maturity, Fair Value, Due after five to ten years | 1,508 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 1,500 | 1,500
Held to Maturity, Fair Value, Total | 1,508 | 1,508
US States and Political Subdivisions Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 0 |
Available for Sale, Amortized Cost, Due after one year to five years | 194 |
Available for Sale, Amortized Cost, Due after five to ten years | 0 |
Available for Sale, Amortized Cost, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 194 | 193
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 0 |
Available for Sale, Fair Value, Due after one year to five years | 195 |
Available for Sale, Fair Value, Due after five to ten years | 0 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 195 | 191
Agency Collateralized Mortgage Obligations [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 0 |
Available for Sale, Amortized Cost, Due after one year to five years | 0 |
Available for Sale, Amortized Cost, Due after five to ten years | 0 |
Available for Sale, Amortized Cost, Due after ten years | 40,483 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 40,483 | 41,874
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 0 |
Available for Sale, Fair Value, Due after one year to five years | 0 |
Available for Sale, Fair Value, Due after five to ten years | 0 |
Available for Sale, Fair Value, Due after ten years | 37,889 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 37,889 | 38,843
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 0 |
Held to Maturity, Amortized Cost, Due after one year to five years | 29,669 |
Held to Maturity, Amortized Cost, Due after five to ten years | 38,862 |
Held to Maturity, Amortized Cost, Due after ten years | 453,090 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 0 |
Held to Maturity, Fair Value, Due after one year to five years | 28,418 |
Held to Maturity, Fair Value, Due after five to ten years | 34,561 |
Held to Maturity, Fair Value, Due after ten years | 387,445 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 521,621 | 535,971
Held to Maturity, Fair Value, Total | 450,424 | 458,417
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 7,201 |
Available for Sale, Amortized Cost, Due after one year to five years | 97,586 |
Available for Sale, Amortized Cost, Due after five to ten years | 98,048 |
Available for Sale, Amortized Cost, Due after ten years | 143,749 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 346,584 | 359,068
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 7,051 |
Available for Sale, Fair Value, Due after one year to five years | 89,002 |
Available for Sale, Fair Value, Due after five to ten years | 84,449 |
Available for Sale, Fair Value, Due after ten years | 125,520 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 306,022 | 313,688
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 81 |
Held to Maturity, Amortized Cost, Due after one year to five years | 215,084 |
Held to Maturity, Amortized Cost, Due after five to ten years | 446,707 |
Held to Maturity, Amortized Cost, Due after ten years | 226,122 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 80 |
Held to Maturity, Fair Value, Due after one year to five years | 204,705 |
Held to Maturity, Fair Value, Due after five to ten years | 398,228 |
Held to Maturity, Fair Value, Due after ten years | 212,541 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 887,994 | 898,927
Held to Maturity, Fair Value, Total | 815,554 | 815,952
US Treasury Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available for Sale, Amortized Cost, Due in one year or less | 99,915 |
Available for Sale, Amortized Cost, Due after one year to five years | 689,740 |
Available for Sale, Amortized Cost, Due after five to ten years | 84,522 |
Available for Sale, Amortized Cost, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 874,177 | 874,035
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 97,018 |
Available for Sale, Fair Value, Due after one year to five years | 632,502 |
Available for Sale, Fair Value, Due after five to ten years | 75,167 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 804,687 | 791,341
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 0 |
Held to Maturity, Amortized Cost, Due after one year to five years | 99,663 |
Held to Maturity, Amortized Cost, Due after five to ten years | 991 |
Held to Maturity, Amortized Cost, Due after ten years | 0 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 0 |
Held to Maturity, Fair Value, Due after one year to five years | 89,875 |
Held to Maturity, Fair Value, Due after five to ten years | 843 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 100,654 | 100,634
Held to Maturity, Fair Value, Total | $ 90,718 | $ 88,879

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