Business Combinations - Additional Information (Detail) - USD ($)		3 Months Ended		12 Months Ended
	Jan. 02, 2019	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Business combination reduction in earnout consideration expense				$ 261,000	$ (550,000)
Goodwill				10,266,000	10,238,000
Viscount Systems, Inc.
Business Acquisition [Line Items]
Date of acquisition completed	Jan. 02, 2019
Business combination, aggregate consideration	$ 2,900,000
Business combination, payment of cash	$ 1,300,000
Business combination, issuance of common stock, shares	419,288
Business combination, issuance of common stock	$ 1,600,000
Business combination, issuance of common stock shares held back	31,447		31,447
Amount of maximum earnout consideration of payable for all periods in shares of common stock	$ 3,500,000
Fair value of earnout consideration	200,000	$ 489,000			$ 750,000
Business combination issued to sellers earnout consideration of shares		157,233
Business combination reduction in earnout consideration expense				$ 261,000
Goodwill	1,200,000
Viscount Systems, Inc. | Maximum
Business Acquisition [Line Items]
Amount of earnout consideration of payable in shares of common stock	3,500,000
Amount of additional earnout consideration of payable in shares of common stock	$ 2,250,000