Consolidated Financial Statement Details - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended
Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2012
Financial Statement Details [Line Items]
Gain related to sale of Alibaba Group Shares	$ 4,603,322	$ 4,603,322	$ 4,603,322

Amount of gain (loss) on sale or disposal of an equity method investment.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration