Annual report pursuant to Section 13 and 15(d)

Common Stock - Computation of Basic and Diluted Net Loss Attributable to Common Shareholders Per Share (Detail)

v2.4.1.9
Common Stock - Computation of Basic and Diluted Net Loss Attributable to Common Shareholders 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 $ (5,682)us-gaap_NetIncomeLoss $ (4,907)us-gaap_NetIncomeLoss $ (7,015)us-gaap_NetIncomeLoss $ (8,636)us-gaap_NetIncomeLoss $ (6,678)us-gaap_NetIncomeLoss $ (10,054)us-gaap_NetIncomeLoss $ (8,420)us-gaap_NetIncomeLoss $ (6,697)us-gaap_NetIncomeLoss $ (26,240)us-gaap_NetIncomeLoss $ (31,849)us-gaap_NetIncomeLoss $ (21,098)us-gaap_NetIncomeLoss
Denominator                      
Weighted average number of common shares outstanding                 18,098,799us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted 14,683,389us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted 13,522,723us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted
Basic and diluted net loss per common share $ (0.26)us-gaap_EarningsPerShareBasicAndDiluted $ (0.23)us-gaap_EarningsPerShareBasicAndDiluted $ (0.47)us-gaap_EarningsPerShareBasicAndDiluted $ (0.59)us-gaap_EarningsPerShareBasicAndDiluted $ (0.45)us-gaap_EarningsPerShareBasicAndDiluted $ (0.68)us-gaap_EarningsPerShareBasicAndDiluted $ (0.57)us-gaap_EarningsPerShareBasicAndDiluted $ (0.46)us-gaap_EarningsPerShareBasicAndDiluted $ (1.45)us-gaap_EarningsPerShareBasicAndDiluted $ (2.17)us-gaap_EarningsPerShareBasicAndDiluted $ (1.56)us-gaap_EarningsPerShareBasicAndDiluted