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Other Investments - Investments without Readily Determinable Fair Value (Details) - USD ($) | 3 Months Ended | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023 | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022
Investments, All Other Investments [Abstract] |  |  |  |  |  |  |
Cost | $ 8,500,000 | $ 8,500,000 |  | $ 8,500,000 |  |  |
Cumulative unrealized gains | 41,900,000 | 41,900,000 |  | 41,900,000 |  |  |
Carrying amount | 50,400,000 | 50,400,000 | $ 50,400,000 | $ 50,400,000 | $ 50,400,000 | $ 50,400,000 | $ 50,400,000
Upward adjustments | 0 | 0 |  |  |  |  |
Downward adjustments | $ 0 | $ 0 |  |  |  |  |

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- Definition Amount of 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 (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479536/321-10-50-3 + 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 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 -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479536/321-10-50-3 + Details
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- Definition Amount of cumulative 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 -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479536/321-10-50-3 + Details
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