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Long-Term Investments - Equity Investments with Carrying Value (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Schedule of Equity and Cost Investments [Line Items] |  |
Long-term investments | $ 5,000 | $ 3,000
Cashido Corp. (Cashido) |  |
Schedule of Equity and Cost Investments [Line Items] |  |
Equity Investments Percentage of Ownership | 0.60% | 0.60%
Vastview Technology, Corp. (Vastview) |  |
Schedule of Equity and Cost Investments [Line Items] |  |
Equity Investments Percentage of Ownership | 2.90% | 2.90%
Deep Vision, Inc (Deep Vision) |  |
Schedule of Equity and Cost Investments [Line Items] |  |
Long-term investments | $ 5,000 | $ 3,000
Equity Investments Percentage of Ownership | 16.20% | 16.20%

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- Definition The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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