Subsequent Events - Additional Information (Detail) (Subsequent Event [Member])	1 Months Ended
Jul. 26, 2013
Subsequent Event [Member]
Subsequent Event [Line Items]
Approved reverse stock split ratio of common stock	1-for-8
Approval date of reverse stock split	May 01, 2013

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 4

-Subparagraph (SAB TOPIC 4.C)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section C

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