Significant Accounting Policies - Depreciation is Calculated on Straight-Line Basis Over Estimated Useful Lives of Assets (Detail)	12 Months Ended
Dec. 31, 2014
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Leasehold improvements	term of the lease
Computer equipment and software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	3 years
Furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	5 years

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=6367646&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=6539997&loc=d3e1205-110223

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