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Investment Securities (Schedule of Available-for-Sale Investment Securities Gross Gains and Gross Losses Realized) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract] |  |  |
Realized gains on investment securities | $ 461,000 | $ 1,252,000 | $ 751,000
Realized losses on investment securities | (22,000) | (173,000) | (530,000)
Net realized gains on investment securities | 439,000 | 1,079,000 | 221,000
Unrealized gains on equity securities with readily determinable fair value | 1,154,000 | 2,688,000 | 4,265,000
Unrealized losses on equity securities with readily determinable fair value | (9,862,000) | (2,411,000) | (3,818,000)
Net unrealized (losses) gains on equity securities with readily determinable fair value | (8,708,000) | 277,000 | 447,000
Upward adjustments of equity securities without readily determinable fair values | 0 | 0 | 401,000
Downward adjustments of equity securities without readily determinable fair values | 0 | 0 | 0
Impairment of equity securities without readily determinable fair values | (12,158,000) | (2,415,000) | (2,995,000)
Adjustment and impairment, net, of equity securities without readily determinable fair values | (12,158,000) | (2,415,000) | (2,594,000)
Losses on investment securities, net | (20,427,000) | (1,059,000) | (1,926,000)
Proceeds from sales of available-for-sale securities | 0 | 192,227,000 | 502,250,000
Proceeds from sales of equity securities with readily determinable fair value | 31,753,000 | 9,759,000 | 6,530,000
Proceeds from sales and capital distributions of equity securities without readily determinable fair value | $ 1,330,000 | $ 2,685,000 | $ 1,857,000

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI https://asc.fasb.org/extlink&oid=126980263&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/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 https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117546-209714 + Details
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