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Investment Securities - Schedule of Gross Gains and Gross Losses Realized and Impairment on Investment Securities (Details) - USD ($) | 3 Months Ended | 9 Months Ended
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Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Realized gains on investment securities | $ 225,000 | $ 15,000 | $ 836,000 | $ 280,000
Realized losses on investment securities | (9,000) | (4,000) | (60,000) | (18,000)
Net realized gains on investment securities | 216,000 | 11,000 | 776,000 | 262,000
Unrealized gains on equity securities with readily determinable fair value | 10,000 | 45,000 | 2,984,000 | 227,000
Unrealized losses on equity securities with readily determinable fair value | (2,094,000) | (3,154,000) | (4,230,000) | (9,809,000)
Net unrealized losses on equity securities with readily determinable fair value | (2,084,000) | (3,109,000) | (1,246,000) | (9,582,000)
Upward 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
Impairment of equity securities without readily determinable fair values | (489,000) | (5,000) | (489,000) | (4,362,000)
Adjustment and impairment, net, of equity securities without readily determinable fair values | (489,000) | (5,000) | (489,000) | (4,362,000)
Losses on investment securities, net | (2,357,000) | (3,103,000) | (959,000) | (13,682,000)
Proceeds from sales of equity securities with readily determinable fair value | 0 | 3,000,000 | 23,592,000 | 21,753,000
Proceeds from sales and capital distributions of equity securities without readily determinable fair value | $ 0 | $ 703,000 | $ 67,000 | $ 1,232,000

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479536/321-10-50-4 + 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/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479536/321-10-50-4 + 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 -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479536/321-10-50-3 + 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 -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479536/321-10-50-3 + Details
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