Acquisitions - Summary of Unaudited Proforma Results of Operation (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Business Acquisition Pro Forma Information [Abstract]
Revenues	$ 11,782	$ 7,389	$ 31,068	$ 21,621
Net income (loss)	$ 3,567	$ (705)	$ 7,051	$ (4,790)
Earnings (loss) per share:
Basic	$ 0.10	$ (0.03)	$ 0.21	$ (0.25)
Diluted	$ 0.09	$ (0.03)	$ 0.20	$ (0.25)

Pro forma basic earnings per share or earnings per unit, which is commonly presented in initial public offerings based on the terms of the offering.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Pro forma diluted earnings per share, which is commonly presented in initial public offerings.

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