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v3.20.4

Investment - Additional Information (Detail) - USD ($) $ in Thousands |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 27, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Jun. 20, 2017
Investment [Line Items] |  |  |  |
Carrying value of investments |  | $ 8,112 | $ 11,192 |
Series Y Preferred Stock [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Impairment on Thesys preferred stock |  | 3,080 |  |
Thesys Group, Inc [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Carrying value of investments |  | $ 0 | 3,080 |
Thesys Group, Inc [Member] | Convertible Preferred Stock [Member] | Series Y Preferred Stock [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Number of shares issued |  |  |  | 7,797,533
Current fully diluted ownership percentage |  |  |  | 19.00%
Securrency Inc [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Ownership interest percentage |  | 25.00% |  |
Original fully diluted ownership interest percentage |  | 20.00% |  |
Percentage of voting approval required to redeem all of the outstanding Series A preferred |  | 60.00% |  |
Securrency Inc [Member] | Convertible Preferred Stock [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Carrying value of investments | $ 8,112 | $ 8,112 | $ 8,112 |
Number of shares purchased | 5,178,488 |  |  |
Non-cumulative dividend | 6.00% |  |  |

X
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