Stockholders' Equity (Summarized Information about Warrants Outstanding) (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Class of Warrant or Right [Line Items]
Granted	574,017
Outstanding, ending balance	90,501	117,461
Stock Purchase Warrants 2009 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2009
Granted	5,589
Exercise price, lower limit	$ 14.67
Exercise price, upper limit	$ 19.61
Fair value of warrants issued	$ 22
Outstanding, ending balance		713
Stock Purchase Warrants 2010 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2010
Granted	51,627
Exercise price, lower limit	$ 20.64
Exercise price, upper limit	$ 27.41
Fair value of warrants issued	351
Outstanding, ending balance	9,199	35,446
Stock Purchase Warrants 2011 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2011
Granted	9,324
Exercise price, lower limit	$ 27.53
Exercise price, upper limit	$ 33.14
Fair value of warrants issued	79
Outstanding, ending balance	9,324	9,324
Stock Purchase Warrants 2012 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2012
Granted	71,978
Exercise price, lower limit	$ 30.52
Exercise price, upper limit	$ 33.03
Fair value of warrants issued	$ 628
Outstanding, ending balance	71,978	71,978