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Securities, Unrealized Gains (Losses) Related to Equity Securities (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 USD ($) Issuer | Jun. 30, 2018 USD ($) Issuer | Dec. 31, 2017 Issuer
Gains and losses on equity securities [Abstract] |  |  |
Net gains and losses recognized on equity securities | $ 91 | $ 163 |
Less: Net gains and losses recognized during the period on equity securities sold during the period | 0 | 44 |
Unrealized gains and losses recognized on equity securities still held | 91 | 119 |
Carrying amount of equity securities without readily determinable fair values | 4,200 | 4,200 |
Impairment adjustments of equity securities without readily determinable fair values | 0 | 0 |
Downward adjustments of equity securities without readily determinable fair values | 0 | 0 |
Upward adjustments of equity securities without readily determinable fair values | $ 0 | $ 0 |
Number of issuers whose holdings exceeded 10% of consolidated stockholders' equity, excluding U.S. Government securities | Issuer | 0 | 0 | 0

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- Definition Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714 + Details
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- Definition Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714 + 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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714 + Details
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- Definition Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714 + Details
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- Definition Amount of impairment loss on investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714 + Details
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- Definition Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714 + Details
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