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Investments - Schedule of Available for Sale Securities Continuous Unrealized Loss Position Fair Value (Details) $ in Thousands | Sep. 30, 2019 USD ($) Number | Dec. 31, 2018 USD ($) Number
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Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 80 | 490
Fair value, Less than 12 months | $ 31,995 | $ 74,366
Unrealized losses, Less than 12 months | (82) | (536)
Fair value, 12 months or longer | 26,553 | 221,001
Unrealized losses, 12 months or longer | (306) | (5,579)
Total, Fair value | 58,548 | 295,367
Total, Unrealized losses | $ (388) | $ (6,115)
U.S. Treasury Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number |  | 1
Fair value, Less than 12 months |  |
Unrealized losses, Less than 12 months |  |
Fair value, 12 months or longer |  | 1,971
Unrealized losses, 12 months or longer |  | (28)
Total, Fair value |  | 1,971
Total, Unrealized losses |  | $ (28)
U.S. Federal Agency Obligations [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number |  | 6
Fair value, Less than 12 months |  | $ 145
Unrealized losses, Less than 12 months |  | (1)
Fair value, 12 months or longer |  | 7,970
Unrealized losses, 12 months or longer |  | (40)
Total, Fair value |  | 8,115
Total, Unrealized losses |  | $ (41)
Municipal Obligations, Tax Exempt [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 35 | 296
Fair value, Less than 12 months | $ 8,105 | $ 35,898
Unrealized losses, Less than 12 months | (27) | (367)
Fair value, 12 months or longer | 5,625 | 85,921
Unrealized losses, 12 months or longer | (53) | (2,403)
Total, Fair value | 13,730 | 121,819
Total, Unrealized losses | $ (80) | $ (2,770)
Municipal Obligations, Taxable [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 7 | 86
Fair value, Less than 12 months |  | $ 8,293
Unrealized losses, Less than 12 months |  | (22)
Fair value, 12 months or longer | 1,551 | 28,984
Unrealized losses, 12 months or longer | (2) | (301)
Total, Fair value | 1,551 | 37,277
Total, Unrealized losses | $ (2) | $ (323)
Agency Mortgage-backed Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 38 | 101
Fair value, Less than 12 months | $ 23,890 | $ 30,030
Unrealized losses, Less than 12 months | (55) | (146)
Fair value, 12 months or longer | 19,377 | 96,155
Unrealized losses, 12 months or longer | (251) | (2,807)
Total, Fair value | 43,267 | 126,185
Total, Unrealized losses | $ (306) | $ (2,953)

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118942371&loc=SL82922954-210456 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 + Details
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