Annual report pursuant to Section 13 and 15(d)

Property and Equipment - Additional Information (Detail)

v2.4.1.9
Property and Equipment - Additional Information (Detail) (USD $)
 12 Months Ended 90 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2013
Property Plant And Equipment [Line Items]          
Depreciation $ 23,000us-gaap_Depreciation $ 17,000us-gaap_Depreciation $ 3,000us-gaap_Depreciation $ 22,000us-gaap_Depreciation $ 61,000us-gaap_Depreciation
Gain (Loss) on Sale of Assets and Asset Impairment Charges 400,000us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges        
Computer Equipment [Member]          
Property Plant And Equipment [Line Items]          
Depreciation         $ 41,000us-gaap_Depreciation
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_ComputerEquipmentMember