Goodwill - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended
Dec. 31, 2012	Mar. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill impairment	$ 2,000,000	$ 2,000,000

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 45

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

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-Name Accounting Standards Codification

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