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Securities, Unrealized Gains (Losses) Related to Equity Securities (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) Issuer | Dec. 31, 2018 USD ($) Issuer
Gains and losses on equity securities [Abstract] |  |
Net gains and losses recognized on equity securities | $ 4,280 | $ 281
Less: Net gains and losses recognized during the period on equity securities sold during the period | 3,966 | 555
Unrealized gains and losses recognized on equity securities still held | 314 | (274)
Equity Securities without Readily Determinable Fair Value, Annual Amount [Abstract] |  |
Impairment adjustments of equity securities without readily determinable fair values | 0 | 0
Carrying amount of equity securities without readily determinable fair values | 4,000 | 4,000
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
Visa Class B Common Stock [Member] |  |
Equity Securities without Readily Determinable Fair Value, Annual Amount [Abstract] |  |
Gain from sale of equity securities without readily determinable fair value | $ 4,000 |

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- Definition Refers to the number of issuers whose holdings exceed 10% of consolidated stockholders' equity, excluding U.S. Government securities. + References No definition available. + 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=116654751&loc=SL75117546-209714 + 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=116654751&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=116654751&loc=SL75117539-209714 + Details
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