Acquisitions - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended
	Dec. 18, 2019	Sep. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
3M's Drive-Thru Communications Systems
Business Acquisition [Line Items]
Business acquisition, purchase price		$ 8,400
Fair value of assets acquired		8,400
Warranty liability assumed		1,400
Business acquisition, cash paid		$ 7,000
Revenue of acquiree			$ 3,500
Restaurant Magic
Business Acquisition [Line Items]
Fair value of assets acquired	$ 47,689
Business acquisition, cash paid	$ 13,000
Percent acquired	100.00%
Consideration	$ 43,005
Equity issued	27,500
Contingent consideration liability			3,300	$ 3,300
Revenue of acquiree			$ 2,200
Subordinate Promissory Note | Restaurant Magic
Business Acquisition [Line Items]
Warranty liability assumed	$ 2,000
Cash Or Subordinated Promissory Notes | Restaurant Magic
Business Acquisition [Line Items]
Percent of contingent consideration	50.00%
Restricted Shares Of Common Stock | Restaurant Magic
Business Acquisition [Line Items]
Percent of contingent consideration	50.00%