Estimated Useful Lives (Detail)	6 Months Ended
Jun. 30, 2017
Computer equipment and software \| Minimum
Property, Plant and Equipment [Line Items]
Property Plant and Equipment Useful Life	3 years
Computer equipment and software \| Maximum
Property, Plant and Equipment [Line Items]
Property Plant and Equipment Useful Life	5 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property Plant and Equipment Useful Life	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property Plant and Equipment Useful Life	Lesser of useful life or lease term

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 35
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68071081&loc=d3e1205-110223

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration