Acquisitions (Unaudited) - Summary of Consideration Paid for Acquisitions (Detail) - Smart Retail [Member] - Subsequent Event [Member] $ in Thousands	Jan. 09, 2019 USD ($)
Business Acquisition [Line Items]
Fair value of assets acquired	$ 9,315
Fair value of liabilities assumed	212
Total purchase price	9,103
Components of purchase price:
Cash	3,974
Common stock	5,129
Total purchase price	$ 9,103

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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