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Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
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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 | $ 1,402,389 | $ 1,459,862
Available for Sale, Fair Value |  |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,272,831 | 1,334,256
Held to Maturity, Fair Value |  |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 1,545,267 | 1,569,107
Held to Maturity, Fair Value, Total | 1,383,621 | 1,417,608
Available for Sale Securities and Held to Maturity Securities Amortized Cost | 2,947,656 |
Debt Securities, Available-for-sale and Held-to-maturity | 2,656,452 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost | 226,495 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value | 220,678 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost | 1,530,817 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value | 1,395,521 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost | 287,108 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value | 252,069 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Amortized Cost | 903,236 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Fair Value | 788,184 |
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 | 199,221 |
Available for Sale, Amortized Cost, Due after five to ten years | 30,792 |
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 | 230,013 | 230,198
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 | 178,800 |
Available for Sale, Fair Value, Due after five to ten years | 26,876 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 205,676 | 207,138
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 29,086 |
Held to Maturity, Amortized Cost, Due after one year to five years | 0 |
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 | 28,243 |
Held to Maturity, Fair Value, Due after one year to five years | 0 |
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 | 29,086 | 29,521
Held to Maturity, Fair Value, Total | 28,243 | 28,408
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 | 52,083 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 52,083 | 53,702
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 | 44,397 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 44,397 | 46,572
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 | 7,688 |
Held to Maturity, Amortized Cost, Due after ten years | 121,333 |
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 | 7,048 |
Held to Maturity, Fair Value, Due after ten years | 114,289 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 129,021 | 130,426
Held to Maturity, Fair Value, Total | 121,337 | 124,653
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 | 197,409 |
Available for Sale, Amortized Cost, Due after one year to five years | 917,338 |
Available for Sale, Amortized Cost, Due after five to ten years | 77,490 |
Available for Sale, Amortized Cost, Due after ten years | 210,152 |
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 192,435 |
Available for Sale, Fair Value, Due after one year to five years | 831,009 |
Available for Sale, Fair Value, Due after five to ten years | 67,617 |
Available for Sale, Fair Value, Due after ten years | 181,770 |
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 29,086 |
Held to Maturity, Amortized Cost, Due after one year to five years | 613,479 |
Held to Maturity, Amortized Cost, Due after five to ten years | 209,618 |
Held to Maturity, Amortized Cost, Due after ten years | 693,084 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 28,243 |
Held to Maturity, Fair Value, Due after one year to five years | 564,512 |
Held to Maturity, Fair Value, Due after five to ten years | 184,452 |
Held to Maturity, Fair Value, Due after ten years | 606,414 |
Held to Maturity, Fair Value, Total | 1,383,621 |
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 | 1,180 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 1,180 | 1,188
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 | 1,036 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,036 | 1,018
Single Issuer Trust Preferred Securities Issued by Banks and Insurers |  |
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 | 1,500 |
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 | 1,372 |
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 | 1,500 | 1,500
Held to Maturity, Fair Value, Total | 1,372 | 1,373
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 | 195 |
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 | 195 | 195
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 | 191 |
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 | 191 | 190
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 | 2,837 |
Available for Sale, Amortized Cost, Due after ten years | 31,807 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 34,644 | 35,713
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 | 2,586 |
Available for Sale, Fair Value, Due after ten years | 29,502 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 32,088 | 33,189
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 | 63,456 |
Held to Maturity, Amortized Cost, Due after five to ten years | 19,228 |
Held to Maturity, Amortized Cost, Due after ten years | 382,332 |
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 | 58,528 |
Held to Maturity, Fair Value, Due after five to ten years | 16,930 |
Held to Maturity, Fair Value, Due after ten years | 317,800 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 465,016 | 477,517
Held to Maturity, Fair Value, Total | 393,258 | 407,911
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 | 1 |
Available for Sale, Amortized Cost, Due after one year to five years | 140,616 |
Available for Sale, Amortized Cost, Due after five to ten years | 43,861 |
Available for Sale, Amortized Cost, Due after ten years | 125,082 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 309,560 | 314,269
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 1 |
Available for Sale, Fair Value, Due after one year to five years | 125,614 |
Available for Sale, Fair Value, Due after five to ten years | 38,155 |
Available for Sale, Fair Value, Due after ten years | 106,835 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 270,605 | 277,047
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 | 448,783 |
Held to Maturity, Amortized Cost, Due after five to ten years | 181,710 |
Held to Maturity, Amortized Cost, Due after ten years | 189,419 |
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 | 414,620 |
Held to Maturity, Fair Value, Due after five to ten years | 159,656 |
Held to Maturity, Fair Value, Due after ten years | 174,325 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 819,912 | 829,431
Held to Maturity, Fair Value, Total | 748,601 | 763,728
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 | 197,408 |
Available for Sale, Amortized Cost, Due after one year to five years | 577,306 |
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 | 774,714 | 824,597
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 192,434 |
Available for Sale, Fair Value, Due after one year to five years | 526,404 |
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 | 718,838 | 769,102
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 | 99,740 |
Held to Maturity, Amortized Cost, Due after five to ten years | 992 |
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 | 89,992 |
Held to Maturity, Fair Value, Due after five to ten years | 818 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 100,732 | 100,712
Held to Maturity, Fair Value, Total | $ 90,810 | $ 91,535

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