v3.19.1

Summary of Significant Accounting Policies; Prior Period Reclassification - Impact of Prior Period Reclassification on Consolidated Statement of Operations (Detail) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Net sales		$ 24,177,000	$ 13,615,000
Cost of sales		19,128,000	12,235,000
Gross profit		5,049,000	1,380,000
Selling, general and administrative expenses		14,700,000	8,094,000
Operating loss		$ (20,047,000)	(6,714,000)
As Originally Reported [Member]
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Net sales			13,615,000
Cost of sales			11,331,000
Gross profit			2,284,000
Selling, general and administrative expenses			8,998,000
Operating loss			(6,714,000)
Effect of Change [Member]
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Cost of sales	$ 904,000		904,000
Gross profit			904,000
Selling, general and administrative expenses			$ (904,000)

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

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