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Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands | Jun. 30, 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 | $ 1,533,336 | $ 1,566,779
Available for Sale, Fair Value |  |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,372,903 | 1,399,154
Held to Maturity, Fair Value |  |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 1,623,892 | 1,705,120
Held to Maturity, Fair Value, Total | 1,444,084 | 1,524,710
Available for Sale Securities and Held to Maturity Securities Amortized Cost | 3,157,228 |
Debt Securities, Available-for-sale and Held-to-maturity | 2,816,987 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost | 157,068 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value | 152,772 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost | 1,343,457 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value | 1,218,330 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost | 641,485 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value | 554,456 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Amortized Cost | 1,015,218 |
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Fair Value | 891,429 |
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 | 141,548 |
Available for Sale, Amortized Cost, Due after five to ten years | 89,022 |
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 | 230,570 | 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 | 125,881 |
Available for Sale, Fair Value, Due after five to ten years | 76,610 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 202,491 | 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 | 30,395 |
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 | 28,488 |
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 | 30,395 | 31,258
Held to Maturity, Fair Value, Total | 28,488 | 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 | 56,061 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 56,061 | 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 | 48,133 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 48,133 | 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 | 6,303 |
Held to Maturity, Amortized Cost, Due after ten years | 127,012 |
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 | 5,680 |
Held to Maturity, Fair Value, Due after ten years | 121,538 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 133,315 | 136,830
Held to Maturity, Fair Value, Total | 127,218 | 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 | 157,045 |
Available for Sale, Amortized Cost, Due after one year to five years | 904,306 |
Available for Sale, Amortized Cost, Due after five to ten years | 238,658 |
Available for Sale, Amortized Cost, Due after ten years | 233,327 |
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 152,749 |
Available for Sale, Fair Value, Due after one year to five years | 813,054 |
Available for Sale, Fair Value, Due after five to ten years | 204,445 |
Available for Sale, Fair Value, Due after ten years | 202,655 |
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 23 |
Held to Maturity, Amortized Cost, Due after one year to five years | 439,151 |
Held to Maturity, Amortized Cost, Due after five to ten years | 402,827 |
Held to Maturity, Amortized Cost, Due after ten years | 781,891 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 23 |
Held to Maturity, Fair Value, Due after one year to five years | 405,276 |
Held to Maturity, Fair Value, Due after five to ten years | 350,011 |
Held to Maturity, Fair Value, Due after ten years | 688,774 |
Held to Maturity, Fair Value, Total | 1,444,084 |
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 | 1,205 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 1,205 | 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 | 1,025 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,025 | 1,034
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 | 1,369 |
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 | 1,369 | 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 | 190 |
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 | 190 | 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 | 3,305 |
Available for Sale, Amortized Cost, Due after ten years | 35,596 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 38,901 | 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 | 2,981 |
Available for Sale, Fair Value, Due after ten years | 32,804 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 35,785 | 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 | 29,508 |
Held to Maturity, Amortized Cost, Due after five to ten years | 38,560 |
Held to Maturity, Amortized Cost, Due after ten years | 438,523 |
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 | 27,911 |
Held to Maturity, Fair Value, Due after five to ten years | 33,774 |
Held to Maturity, Fair Value, Due after ten years | 366,962 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 506,591 | 535,971
Held to Maturity, Fair Value, Total | 428,647 | 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 | 7,144 |
Available for Sale, Amortized Cost, Due after one year to five years | 87,582 |
Available for Sale, Amortized Cost, Due after five to ten years | 96,895 |
Available for Sale, Amortized Cost, Due after ten years | 140,465 |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 332,086 | 359,068
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 7,024 |
Available for Sale, Fair Value, Due after one year to five years | 78,115 |
Available for Sale, Fair Value, Due after five to ten years | 81,586 |
Available for Sale, Fair Value, Due after ten years | 120,693 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 287,418 | 313,688
Held to Maturity, Amortized Cost |  |
Held to Maturity, Amortized Cost, Due in one year or less | 23 |
Held to Maturity, Amortized Cost, Due after one year to five years | 278,067 |
Held to Maturity, Amortized Cost, Due after five to ten years | 356,972 |
Held to Maturity, Amortized Cost, Due after ten years | 216,356 |
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Due in one year or less | 23 |
Held to Maturity, Fair Value, Due after one year to five years | 259,168 |
Held to Maturity, Fair Value, Due after five to ten years | 309,733 |
Held to Maturity, Fair Value, Due after ten years | 200,274 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 851,418 | 898,927
Held to Maturity, Fair Value, Total | 769,198 | 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 | 149,901 |
Available for Sale, Amortized Cost, Due after one year to five years | 674,982 |
Available for Sale, Amortized Cost, Due after five to ten years | 49,436 |
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 | 874,319 | 874,035
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 145,725 |
Available for Sale, Fair Value, Due after one year to five years | 608,868 |
Available for Sale, Fair Value, Due after five to ten years | 43,268 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 797,861 | 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 | 99,681 |
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 | 88,340 |
Held to Maturity, Fair Value, Due after five to ten years | 824 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 100,673 | 100,634
Held to Maturity, Fair Value, Total | $ 89,164 | $ 88,879

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