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Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Available for Sale, Fair Value |  |
Debt Securities, Available-for-sale, Amortized Cost | $ 450,495 | $ 448,219
Held to Maturity, Amortized Cost |  |
Held to maturity Securities, Amortized Cost | 553,705 | 497,688
Held to Maturity, Fair Value |  |
Held to Maturity, Fair Value, Total | 534,622 | 494,194
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 | 20,012 |
Available for Sale, Amortized Cost, Due after five to ten years | 12,467 |
Available for Sale, Amortized Cost, Due after ten years | 0 |
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 | 19,728 |
Available for Sale, Fair Value, Due after five to ten years | 11,844 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 32,479 | 35,475
Available for sale Securities, Fair Value, Total | 31,572 |
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 | 55,961 |
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 | 54,336 |
Debt Securities, Available-for-sale, Amortized Cost | 55,961 | 47,852
Available for sale Securities, Fair Value, Total | 54,336 |
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 | 0 |
Held to Maturity, Amortized Cost, Due after ten years | 25,376 |
Held to maturity Securities, Amortized Cost | 25,376 | 27,416
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 | 0 |
Held to Maturity, Fair Value, Due after ten years | 24,522 |
Held to Maturity, Fair Value, Total | 24,522 | 27,399
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 | 278 |
Available for Sale, Amortized Cost, Due after one year to five years | 65,948 |
Available for Sale, Amortized Cost, Due after five to ten years | 112,857 |
Available for Sale, Amortized Cost, Due after ten years | 271,412 |
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 281 |
Available for Sale, Fair Value, Due after one year to five years | 64,448 |
Available for Sale, Fair Value, Due after five to ten years | 109,469 |
Available for Sale, Fair Value, Due after ten years | 261,663 |
Available for sale Securities, Fair Value, Total | 435,861 |
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 | 13,446 |
Held to Maturity, Amortized Cost, Due after five to ten years | 39,914 |
Held to Maturity, Amortized Cost, Due after ten years | 500,345 |
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 | 13,197 |
Held to Maturity, Fair Value, Due after five to ten years | 38,907 |
Held to Maturity, Fair Value, Due after ten years | 482,518 |
Held to Maturity, Fair Value, Total | 534,622 |
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 | 2,159 |
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 | 1,800 |
Debt Securities, Available-for-sale, Amortized Cost | 2,159 | 2,179
Available for sale Securities, Fair Value, Total | 1,800 |
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [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 | 1,000 |
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 | 1,004 |
Debt Securities, Available-for-sale, Amortized Cost | 1,000 | 2,012
Available for sale Securities, Fair Value, Total | 1,004 |
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 Securities, Amortized Cost | 1,500 | 1,500
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 | 1,490 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Held to Maturity, Fair Value, Total | 1,490 | 1,529
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 | 1,022 |
Available for Sale, Amortized Cost, Due after five to ten years | 951 |
Available for Sale, Amortized Cost, Due after ten years | 0 |
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 | 1,023 |
Available for Sale, Fair Value, Due after five to ten years | 958 |
Available for Sale, Fair Value, Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 1,973 | 2,237
Available for sale Securities, Fair Value, Total | 1,981 |
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 | 143,764 |
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 | 137,645 |
Debt Securities, Available-for-sale, Amortized Cost | 143,764 | 124,098
Available for sale Securities, Fair Value, Total | 137,645 |
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 | 941 |
Held to Maturity, Amortized Cost, Due after ten years | 335,405 |
Held to maturity Securities, Amortized Cost | 336,346 | 262,998
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 | 936 |
Held to Maturity, Fair Value, Due after ten years | 322,580 |
Held to Maturity, Fair Value, Total | 323,516 | 258,408
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 | 278 |
Available for Sale, Amortized Cost, Due after one year to five years | 44,914 |
Available for Sale, Amortized Cost, Due after five to ten years | 99,439 |
Available for Sale, Amortized Cost, Due after ten years | 68,528 |
Available for Sale, Fair Value |  |
Available for Sale, Fair Value, Due in one year or less | 281 |
Available for Sale, Fair Value, Due after one year to five years | 43,697 |
Available for Sale, Fair Value, Due after five to ten years | 96,667 |
Available for Sale, Fair Value, Due after ten years | 66,878 |
Debt Securities, Available-for-sale, Amortized Cost | 213,159 | 214,934
Available for sale Securities, Fair Value, Total | 207,523 |
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 | 12,442 |
Held to Maturity, Amortized Cost, Due after five to ten years | 37,473 |
Held to Maturity, Amortized Cost, Due after ten years | 139,564 |
Held to maturity Securities, Amortized Cost | 189,479 | 204,768
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 | 12,191 |
Held to Maturity, Fair Value, Due after five to ten years | 36,481 |
Held to Maturity, Fair Value, Due after ten years | 135,416 |
Held to Maturity, Fair Value, Total | 184,088 | 205,823
US Treasury Securities [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 | 1,004 |
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 Securities, Amortized Cost | 1,004 | 1,006
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 | 1,006 |
Held to Maturity, Fair Value, Due after five to ten years | 0 |
Held to Maturity, Fair Value, Due after ten years | 0 |
Held to Maturity, Fair Value, Total | 1,006 | 1,035
Equity Securities [Member] |  |
Available for Sale, Fair Value |  |
Debt Securities, Available-for-sale, Amortized Cost | $ 0 | $ 19,432

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