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Investments - Details of Investments Carried at Cost (Detail) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
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Securrency Inc. - Carrying Value [Member] |  |
Investments | $ 13,849 | $ 8,112
Securrency Inc. - Cost [Member] |  |
Investments | 13,612 | 8,112
Securrency Inc. - Series A Convertible Preferred Stock - Carrying Value [Member] |  |
Investments | 8,349 | 8,112
Securrency Inc. - Series A Convertible Preferred Stock - Cost [Member] |  |
Investments | 8,112 | 8,112
Securrency Inc. - Series B Convertible Preferred Stock - Carrying Value [Member] |  |
Investments | 5,500 | 0
Securrency Inc. - Series B Convertible Preferred Stock - Cost [Member] |  |
Investments | $ 5,500 | $ 0

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- Definition Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments. + References No definition available. + Details
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