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Securities, Available for Sale (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | $ 968,554 | $ 1,017,626 |
Unrealized gains | 8,319 | 1,216 |
Unrealized losses | 1,533 | 20,346 |
Estimated fair value | 975,340 | 998,496 |
Components of net realized gains (losses) on sale of AFS securities [Abstract] |  |  |
Gross realized gains | 73 | 0 | $ 2,241
Gross realized (losses) | (152) | (6,622) | (372)
Net AFS realized (losses) gains | (79) | (6,622) | 1,869
Gains from calls on securities available for sale | 25 | 0 | 100
OTTI loss realized on equity investment | 0 | 0 | $ 1,300
Federal Agency [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 34,998 | 84,982 |
Unrealized gains | 3 | 10 |
Unrealized losses | 243 | 693 |
Estimated fair value | 34,758 | 84,299 |
State & Municipal [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 2,533 | 30,136 |
Unrealized gains | 0 | 16 |
Unrealized losses | 20 | 237 |
Estimated fair value | 2,513 | 29,915 |
Mortgage-Backed, Government Sponsored Enterprises [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 453,614 | 493,225 |
Unrealized gains | 4,982 | 439 |
Unrealized losses | 239 | 10,354 |
Estimated fair value | 458,357 | 483,310 |
Mortgage-backed Securities, U.S. Government Agency Securities [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 44,758 | 29,190 |
Unrealized gains | 667 | 270 |
Unrealized losses | 156 | 475 |
Estimated fair value | 45,269 | 28,985 |
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 328,499 | 332,409 |
Unrealized gains | 1,949 | 344 |
Unrealized losses | 467 | 7,211 |
Estimated fair value | 329,981 | 325,542 |
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 104,152 | 47,684 |
Unrealized gains | 718 | 137 |
Unrealized losses | 408 | 1,376 |
Estimated fair value | $ 104,462 | $ 46,445 |

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- Definition Gains from calls (requests of early payments) on trading securities which are classified as available-for-sale securities. + References No definition available. + Details
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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 + Details
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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563 + Details
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563 + Details
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