Property and Equipment Estimated Useful Life (Detail)	12 Months Ended
Dec. 31, 2012
Office Equipment and Furniture \| Maximum
Property, Plant and Equipment [Line Items]
Property and Equipment Estimated Useful Life	7 years
Office Equipment and Furniture \| Minimum
Property, Plant and Equipment [Line Items]
Property and Equipment Estimated Useful Life	5 years
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and Equipment Estimated Useful Life	3 years
Computer Equipment
Property, Plant and Equipment [Line Items]
Property and Equipment Estimated Useful Life	3 years

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

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