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Securities, Unrealized Gains (Losses) Related to Equity Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Gains (losses) on equity securities [Abstract] |  |  |  |  |
Net gains and (losses) recognized on equity securities | $ 73 | $ 4,012 | $ (565) | $ 4,099 |
Less: Net gains and (losses) recognized during the period on equity securities sold during the period | 0 | 3,966 | 0 | 3,966 |
Unrealized gains and (losses) recognized on equity securities still held | 73 | 46 | (565) | 133 |
Carrying amount of equity securities without readily determinable fair values | 4,000 |  | 4,000 |  | $ 4,000
Impairment adjustments of equity securities without readily determinable fair values | 0 | 0 | 0 | 0 |
Downward adjustments of equity securities without readily determinable fair values | 0 | 0 | 0 | 0 |
Upward adjustments of equity securities without readily determinable fair values | $ 0 | 0 | $ 0 | 0 |
Visa Class B Common Stock [Member] |  |  |  |  |
Gains (losses) on equity securities [Abstract] |  |  |  |  |
Gain from sale of equity securities without readily determinable fair value |  | $ 4,000 |  | $ 4,000 |

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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=120269885&loc=SL75117546-209714 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + Details
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