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Securities, Held to Maturity (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
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Held-to-maturity securities, fair value to amortized cost [Abstract] |  |
Amortized cost | $ 621,359 | $ 630,074
Unrealized gains | 21,085 | 11,817
Unrealized losses | 119 | 629
Estimated fair value | 642,325 | 641,262
Allowance for credit losses on HTM securities | 0 |
Amortized costs of securities available for sale and held to maturity pledged | 1,400,000 | 1,300,000
Amortized costs of securities AFS and HTM pledged as collateral for repurchase agreements | 270,500 | 189,800
Mortgage-Backed, Government Sponsored Enterprises [Member] |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |
Amortized cost | 151,588 | 149,448
Unrealized gains | 7,020 | 3,184
Unrealized losses | 0 | 155
Estimated fair value | 158,608 | 152,477
Mortgage-Backed, U.S. Government Agency Securities [Member] |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |
Amortized cost | 12,236 | 13,667
Unrealized gains | 815 | 584
Unrealized losses | 0 | 0
Estimated fair value | 13,051 | 14,251
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member] |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |
Amortized cost | 171,397 | 189,402
Unrealized gains | 5,990 | 2,165
Unrealized losses | 0 | 368
Estimated fair value | 177,387 | 191,199
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member] |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |
Amortized cost | 105,704 | 110,498
Unrealized gains | 4,133 | 3,256
Unrealized losses | 0 | 100
Estimated fair value | 109,837 | 113,654
State & Municipal [Member] |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |
Amortized cost | 180,434 | 167,059
Unrealized gains | 3,127 | 2,628
Unrealized losses | 119 | 6
Estimated fair value | $ 183,442 | $ 169,681

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- Definition This represents the amortized costs of securities available for sale and held to maturity that are pledged as collateral for securities sold under repurchase agreements. + References No definition available. + Details
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- Definition Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aaa) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
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