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Contractural maturities (Details 3) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Available for Sale, Fair Value |  |
Debt Securities, Available-for-sale, Amortized Cost | $ 450,548 |
Debt Securities, Available-for-sale | 442,752 | $ 447,498
Held to Maturity, Amortized Cost |  |
Amortized Cost | 611,490 | 497,688
Held to Maturity, Fair Value |  |
Fair Value | 603,640 | 494,194
U.S. Government agency securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 20,010 |
Due after five to ten years | 12,467 |
Due after ten years | 0 |
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 19,903 |
Due after five to ten years | 12,135 |
Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 32,477 | 35,475
Debt Securities, Available-for-sale | 32,038 | 35,430
Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 89 |
Due after one year to five years | 73,232 |
Due after five to ten years | 102,824 |
Due after ten years | 274,403 |
Available for Sale, Fair Value |  |
Due in one year or less | 90 |
Due in one year or less | 72,435 |
Due after five to ten years | 101,501 |
Due after ten years | 268,726 |
Securities - available for sale | 442,752 |
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 13,102 |
Due after five to ten years | 37,938 |
Due after ten years | 560,450 |
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 12,981 |
Due after five to ten years | 37,532 |
Due after ten years | 553,127 |
Fair Value | 603,640 |
US Treasury Securities [Member] |  |
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 1,004 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Amortized Cost | 1,004 | 1,006
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 1,015 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Fair Value | 1,015 | 1,035
Agency mortgage-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 89 |
Due after one year to five years | 52,452 |
Due after five to ten years | 89,408 |
Due after ten years | 80,542 |
Available for Sale, Fair Value |  |
Due in one year or less | 90 |
Due in one year or less | 51,761 |
Due after five to ten years | 88,402 |
Due after ten years | 79,852 |
Debt Securities, Available-for-sale, Amortized Cost | 222,491 | 214,934
Debt Securities, Available-for-sale | 220,105 | 215,764
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 12,098 |
Due after five to ten years | 35,703 |
Due after ten years | 204,683 |
Amortized Cost | 252,484 | 204,768
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 11,966 |
Due after five to ten years | 35,310 |
Due after ten years | 203,652 |
Fair Value | 250,928 | 205,823
Agency collateralized mortgage obligations [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 138,149 |
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 134,911 |
Debt Securities, Available-for-sale, Amortized Cost | 138,149 | 124,098
Debt Securities, Available-for-sale | 134,911 | 122,012
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 735 |
Due after ten years | 332,040 |
Amortized Cost | 332,775 | 262,998
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 732 |
Due after ten years | 325,992 |
Fair Value | 326,724 | 258,408
US States and Political Subdivisions Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 770 |
Due after five to ten years | 949 |
Due after ten years | 0 |
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 771 |
Due after five to ten years | 964 |
Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 1,719 | 2,237
Debt Securities, Available-for-sale | 1,735 | 2,274
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Amortized Cost | 0 |
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Fair Value | 0 |
Single issuer trust preferred securities issued by banks [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 717 |
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 707 |
Debt Securities, Available-for-sale, Amortized Cost | 717 | 2,012
Debt Securities, Available-for-sale | 707 | 2,016
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 1,500 |
Due after ten years | 0 |
Amortized Cost | 1,500 | 1,500
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 1,490 |
Due after ten years | 0 |
Fair Value | 1,490 | 1,529
Pooled Trust Preferred Securities Issued By Banks And Insurers [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 1,678 |
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 1,329 |
Debt Securities, Available-for-sale, Amortized Cost | 1,678 | 2,179
Debt Securities, Available-for-sale | 1,329 | 1,640
Small Business Administration Pooled Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 53,317 |
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 51,927 |
Debt Securities, Available-for-sale, Amortized Cost | 53,317 | 47,852
Debt Securities, Available-for-sale | 51,927 | 47,778
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 23,727 |
Amortized Cost | 23,727 | 27,416
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 23,483 |
Fair Value | $ 23,483 | $ 27,399

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62586-112803 + Details
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