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Investments - Equity Securities (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2017
Equity Securities, FV-NI, Gain (Loss) [Abstract] |  |
Cost | $ 4,134 |
Gross Gains | 3,667 |
Gross Losses | (81) |
Fair Value | 7,720 |
Unrealized Gain (Loss) on Equity Securities [Abstract] |  |
Cost |  | $ 7,223
Gross Gains |  | 39
Gross Losses |  | (16)
Fair Value |  | $ 7,246
Recognized net gains on equity securities still held | $ 3,600 |

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- Definition Equity Securities, FV-NI, Gain (Loss) [Abstract] + References No definition available. + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References No definition available. + Details
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- Definition Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. + References No definition available. + Details
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- Definition Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References No definition available. + Details
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- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References No definition available. + Details
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- Definition Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + 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 equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for 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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- Definition Amount of equity securities categorized neither as held-to-maturity nor as trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62557-112803 + Details
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