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Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | $ 304,915 | $ 356,059
Gross unrealized gains | 9,707 | 7,266
Gross unrealized losses | (133) | (327)
Estimated fair value | 314,489 | 362,998
U.S. Treasury Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 2,000 | 2,300
Gross unrealized gains | 57 | 16
Gross unrealized losses |  |
Estimated fair value | 2,057 | 2,316
U.S. Federal Agency Obligations [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 2,015 | 4,015
Gross unrealized gains | 148 | 91
Gross unrealized losses |  |
Estimated fair value | 2,163 | 4,106
Municipal Obligations, Tax Exempt [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 138,118 | 142,391
Gross unrealized gains | 3,626 | 3,513
Gross unrealized losses | (61) | (42)
Estimated fair value | 141,683 | 145,862
Municipal Obligations, Taxable [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 48,307 | 45,541
Gross unrealized gains | 1,822 | 1,293
Gross unrealized losses | (72) | (55)
Estimated fair value | 50,057 | 46,779
Agency Mortgage-backed Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 112,570 | 159,908
Gross unrealized gains | 4,054 | 2,353
Gross unrealized losses |  | (230)
Estimated fair value | 116,624 | 162,031
Certificates of Deposit [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 1,905 | 1,904
Gross unrealized gains |  |
Gross unrealized losses |  |
Estimated fair value | $ 1,905 | $ 1,904

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References No definition available. + Details
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as 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=121645371&loc=d3e27161-111563 + Details
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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