Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Property and equipment	$ 63,048	$ 30,267
Accumulated amortization and depreciation	(19,650)	(11,185)
Property and equipment, net	43,398	19,082
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment	15,466	10,080
Delivery equipment
Property Plant And Equipment [Line Items]
Property and equipment	1,904	555
Furniture and fixtures
Property Plant And Equipment [Line Items]
Property and equipment	4,776	2,092
Developed software
Property Plant And Equipment [Line Items]
Property and equipment	21,758	11,129
Purchased Software And Digital Assets
Property Plant And Equipment [Line Items]
Property and equipment	1,050	361
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment	15,547	$ 6,050
Construction in progress
Property Plant And Equipment [Line Items]
Property and equipment	$ 2,547

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Subparagraph (SX 210.5-02(13))
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