Summary of Company's Warrants Outstanding (Detail)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Class of Warrant or Right [Line Items]
Outstanding Warrants	633,740	791,508	3,093,676	3,127,618
Minimum of Price Range
Class of Warrant or Right [Line Items]
Warrants Outstanding, Issue Date	Jan. 30, 2009
Exercise Price of warrants issued	6.96
Outstanding Warrants	129,768
Warrant expiration date	Jul. 30, 2014
Maximum of Price Range
Class of Warrant or Right [Line Items]
Warrants Outstanding, Issue Date	Aug. 25, 2009
Exercise Price of warrants issued	10.68
Outstanding Warrants	503,972
Warrant expiration date	Aug. 31, 2014