Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Line Items]
Property and equipment	$ 116,780	$ 69,248
Accumulated amortization and depreciation	(45,396)	(22,693)
Property and equipment, net	71,384	46,555
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment	31,601	17,548
Furniture and fixtures
Property Plant And Equipment [Line Items]
Property and equipment	6,857	4,842
Developed software
Property Plant And Equipment [Line Items]
Property and equipment	52,041	26,460
Purchased Software and Digital Assets
Property Plant And Equipment [Line Items]
Property and equipment	2,881	1,360
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment	$ 23,400	$ 19,038

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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-Section S99
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-Subparagraph (SX 210.5-02(13))
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