Annual report pursuant to Section 13 and 15(d)

Net (Income) Loss Per Common Share - Reconciliation of Numerator and Denominator (Detail)

v2.4.1.9
Net (Income) Loss Per Common Share - Reconciliation of Numerator and Denominator (Detail) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Numerator:                      
Net income (loss) - basic $ (5,964)us-gaap_NetIncomeLoss $ (7,745)us-gaap_NetIncomeLoss $ (766)us-gaap_NetIncomeLoss $ (7,109)us-gaap_NetIncomeLoss $ (7,589)us-gaap_NetIncomeLoss $ 1,176us-gaap_NetIncomeLoss $ (12,788)us-gaap_NetIncomeLoss $ (9,214)us-gaap_NetIncomeLoss $ (21,584)us-gaap_NetIncomeLoss $ (28,415)us-gaap_NetIncomeLoss $ (71,135)us-gaap_NetIncomeLoss
Less: noncash income from change in fair value of common stock warrants                 9,344us-gaap_DilutiveSecuritiesEffectOnBasicEarningsPerShareOther    
Net loss - diluted                 $ (30,928)us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted $ (28,415)us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted $ (71,135)us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted
Denominator:                      
Weighted-average number of common shares outstanding                 60,335us-gaap_WeightedAverageNumberOfSharesOutstandingBasic 57,832us-gaap_WeightedAverageNumberOfSharesOutstandingBasic 54,219us-gaap_WeightedAverageNumberOfSharesOutstandingBasic
Dilutive effect of warrants                 3,051us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants    
Weighted-average common shares outstanding and dilutive potential common share-diluted                 63,386us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding 57,832us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding 54,219us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding
Net loss per share:                      
Basic $ (0.09)us-gaap_EarningsPerShareBasic $ (0.13)us-gaap_EarningsPerShareBasic $ (0.01)us-gaap_EarningsPerShareBasic $ (0.12)us-gaap_EarningsPerShareBasic $ (0.13)us-gaap_EarningsPerShareBasic $ 0.02us-gaap_EarningsPerShareBasic $ (0.22)us-gaap_EarningsPerShareBasic $ (0.16)us-gaap_EarningsPerShareBasic $ (0.36)us-gaap_EarningsPerShareBasic $ (0.49)us-gaap_EarningsPerShareBasic $ (1.31)us-gaap_EarningsPerShareBasic
Diluted $ (0.12)us-gaap_EarningsPerShareDiluted $ (0.15)us-gaap_EarningsPerShareDiluted $ (0.12)us-gaap_EarningsPerShareDiluted $ (0.14)us-gaap_EarningsPerShareDiluted $ (0.13)us-gaap_EarningsPerShareDiluted $ (0.08)us-gaap_EarningsPerShareDiluted $ (0.22)us-gaap_EarningsPerShareDiluted $ (0.16)us-gaap_EarningsPerShareDiluted $ (0.49)us-gaap_EarningsPerShareDiluted $ (0.49)us-gaap_EarningsPerShareDiluted $ (1.31)us-gaap_EarningsPerShareDiluted