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Investments - Schedule of Amortized Cost and Fair Value of Securities Available-for-sale (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Available for sale: |  |
Amortized Cost | $ 185,749 | $ 247,607
Gross Unrealized Gains | 119 | 650
Gross Unrealized Losses | (7,723) | (4,169)
Available-for-sale investments | 178,145 | 244,088
Mortgage-backed securities |  |
Available for sale: |  |
Amortized Cost | 167,203 | 227,607
Gross Unrealized Gains | 119 | 650
Gross Unrealized Losses | (6,906) | (3,210)
Available-for-sale investments | 160,416 | 225,047
Utah Housing Corporation bonds |  |
Available for sale: |  |
Amortized Cost | 18,546 | 20,000
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (817) | (959)
Available-for-sale investments | $ 17,729 | $ 19,041

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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=82897076&loc=d3e27161-111563 + Details
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