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Investments - Schedule of Available for Sale Securities Continuous Unrealized Loss Position Fair Value (Details) $ in Thousands | Jun. 30, 2019 USD ($) Number | Dec. 31, 2018 USD ($) Number
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Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 104 | 490
Fair value, Less than 12 months | $ 1,110 | $ 74,366
Unrealized losses, Less than 12 months | (1) | (536)
Fair value, 12 months or longer | 67,858 | 221,001
Unrealized losses, 12 months or longer | (784) | (5,579)
Total, Fair value | 68,968 | 295,367
Total, Unrealized losses | $ (785) | $ (6,115)
U.S. Federal Agency Obligations [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 2 | 6
Fair value, Less than 12 months |  | $ 145
Unrealized losses, Less than 12 months |  | (1)
Fair value, 12 months or longer | 2,498 | 7,970
Unrealized losses, 12 months or longer | (2) | (40)
Total, Fair value | 2,498 | 8,115
Total, Unrealized losses | $ (2) | $ (41)
Municipal Obligations, Tax Exempt [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 57 | 296
Fair value, Less than 12 months |  | $ 35,898
Unrealized losses, Less than 12 months |  | (367)
Fair value, 12 months or longer | 21,874 | 85,921
Unrealized losses, 12 months or longer | (227) | (2,403)
Total, Fair value | 21,874 | 121,819
Total, Unrealized losses | $ (227) | $ (2,770)
Municipal Obligations, Taxable [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 18 | 86
Fair value, Less than 12 months | $ 1,110 | $ 8,293
Unrealized losses, Less than 12 months | (1) | (22)
Fair value, 12 months or longer | 5,760 | 28,984
Unrealized losses, 12 months or longer | (10) | (301)
Total, Fair value | 6,870 | 37,277
Total, Unrealized losses | $ (11) | $ (323)
Agency Mortgage-backed Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
No. of securities | Number | 27 | 101
Fair value, Less than 12 months |  | $ 30,030
Unrealized losses, Less than 12 months |  | (146)
Fair value, 12 months or longer | 37,726 | 96,155
Unrealized losses, 12 months or longer | (545) | (2,807)
Total, Fair value | 37,726 | 126,185
Total, Unrealized losses | $ (545) | $ (2,953)
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)

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References No definition available. + Details
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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 + Details
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