Annual report pursuant to Section 13 and 15(d)

Net Loss Per Common Share - Calculation of Basic and Diluted Net Loss Per Share (Detail)

v2.4.1.9
Net Loss Per Common Share - Calculation of Basic and Diluted Net Loss Per Share (Detail) (USD $)
In Thousands, except 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 loss $ (3,713)us-gaap_NetIncomeLoss $ (4,592)us-gaap_NetIncomeLoss $ (4,711)us-gaap_NetIncomeLoss $ (7,370)us-gaap_NetIncomeLoss $ (9,798)us-gaap_NetIncomeLoss $ (7,832)us-gaap_NetIncomeLoss $ (10,670)us-gaap_NetIncomeLoss $ (8,858)us-gaap_NetIncomeLoss $ (20,386)us-gaap_NetIncomeLoss $ (37,158)us-gaap_NetIncomeLoss $ (27,610)us-gaap_NetIncomeLoss
Denominator                      
Weighted-average common shares outstanding— Denominator for basic and diluted net loss per share                 36,323,596us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted 30,429,743us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted 21,654,984us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted
Basic and diluted net loss per share attributed to common stockholders $ (0.10)us-gaap_EarningsPerShareBasicAndDiluted $ (0.13)us-gaap_EarningsPerShareBasicAndDiluted $ (0.13)us-gaap_EarningsPerShareBasicAndDiluted $ (0.21)us-gaap_EarningsPerShareBasicAndDiluted $ (0.27)us-gaap_EarningsPerShareBasicAndDiluted $ (0.24)us-gaap_EarningsPerShareBasicAndDiluted $ (0.38)us-gaap_EarningsPerShareBasicAndDiluted $ (0.35)us-gaap_EarningsPerShareBasicAndDiluted $ (0.56)us-gaap_EarningsPerShareBasicAndDiluted $ (1.22)us-gaap_EarningsPerShareBasicAndDiluted $ (1.27)us-gaap_EarningsPerShareBasicAndDiluted