Acquisitions - Schedule of Purchase Price Allocation (Parenthetical) (Detail) (Developed technology [Member])	9 Months Ended
Sep. 30, 2013
Developed technology [Member]
Business Acquisition [Line Items]
Finite lived intangible asset useful life	3 years

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration