Revenue, Segment and Geographic Information - Schedule of (Loss) Income from Operations by Reporting Segments (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenue	$ 12,976,058	$ 14,938,964	$ 37,961,023	$ 39,883,099
Cost of revenues	(8,074,445)	(9,909,045)	(26,338,527)	(27,028,399)
Gross profit	$ 4,901,613	$ 5,029,919	$ 11,622,496	$ 12,854,700
Gross margin %	37.80%	33.70%	30.60%	32.20%
Total operating expenses	$ 3,922,171	$ 4,610,362	$ 12,560,094	$ 15,447,831
Income (loss) from operations	979,442	419,557	(937,598)	(2,593,131)
OSS Segment
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenue	8,976,539	9,735,630	24,722,066	26,167,536
Cost of revenues	(4,976,063)	(5,937,592)	(15,899,150)	(16,442,130)
Gross profit	$ 4,000,476	$ 3,798,038	$ 8,822,916	$ 9,725,406
Gross margin %	44.60%	39.00%	35.70%	37.20%
Total operating expenses	$ 3,052,949	$ 3,730,788	$ 9,883,997	$ 12,703,649
Income (loss) from operations	947,527	67,250	(1,061,081)	(2,978,243)
Bressner Segment
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenue	3,999,519	5,203,334	13,238,957	13,715,563
Cost of revenues	(3,098,382)	(3,971,453)	(10,439,377)	(10,586,269)
Gross profit	$ 901,137	$ 1,231,881	$ 2,799,580	$ 3,129,294
Gross margin %	22.50%	23.70%	21.10%	22.80%
Total operating expenses	$ 869,222	$ 879,574	$ 2,676,097	$ 2,744,182
Income (loss) from operations	$ 31,915	$ 352,307	$ 123,483	$ 385,112

Gross profit percentage.

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The aggregate cost of goods produced and sold and services rendered during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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