Litigation and Other Contingencies - Additional Information (Detail)	May 21, 2018 Stockholder	Jun. 30, 2018 USD ($)
Loss Contingencies [Line Items]
Number of stockholders filed putative class action complaints \| Stockholder	3
Sales tax liability		$ 500,000
Sales tax reserve		100,000
Sales tax collections from customers, current		400,000
Indemnification Agreement [Member]
Loss Contingencies [Line Items]
Recorded liabilities corresponding to agreements		$ 0

Number of stockholders filed putative class action complaints.

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Sales and excise tax reserve.

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Sales tax collections from customers current.

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Amount of loss contingency liability.

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Carrying value as of the balance sheet date of liabilities incurred through that date and payable for statutory sales and use taxes, including value added tax.

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