Quarterly Information (Unaudited) - Statement of Operations Data (Parenthetical) (Detail) (USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Schedule Of Quarterly Financial Information [Line Items]      
Valuation allowance, reversed $ 373,000 $ (677,000) $ 933,000
Xively [Member]
     
Schedule Of Quarterly Financial Information [Line Items]      
Valuation allowance, reversed   $ (677,000)