SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Accounts receivable (Details) - USD ($) |
12 Months Ended | |||
|---|---|---|---|---|
Jun. 09, 2014 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Allowance rollforward | ||||
| Balance at beginning of year | $ 1,545,000 | $ 1,528,000 | ||
| Provision | 211,696 | 54,939 | $ 618,786 | |
| Write-offs | (105,000) | (38,000) | ||
| Balance at end of year | 1,652,000 | 1,545,000 | $ 1,528,000 | |
| Unbilled receivables, current | $ 615,000 | $ 1,860,000 | ||
| Estimated residual value | $ 1,085,000 | |||
| Asset impairment | 2,500,000 | |||
| Insurance receivable | $ 2,500,000 | |||
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- Definition Amount of allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of residual asset covered by residual value guarantee. Excludes guarantee considered to be lease payments for lessor. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer. No definition available.
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