Equity - Additional Information - Exercise of Warrants (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended		12 Months Ended				1 Months Ended		12 Months Ended		1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended	1 Months Ended
	May 18, 2012	Nov. 15, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jul. 17, 2012	Oct. 03, 2012 Executive Officer [Member]	Nov. 15, 2011 Series A Warrants [Member]	Dec. 31, 2011 Series A Warrants [Member]	Dec. 31, 2007 Series A Warrants [Member]	Nov. 15, 2011 Series B Warrants [Member]	Dec. 31, 2007 Series B Warrants [Member]	May 18, 2012 Warrants [Member]	Dec. 31, 2012 Warrants [Member]	May 18, 2012 Repurchase [Member]
Class of Warrant or Right [Line Items]
Original Value of shares repurchased during cashless exercise	$ 754		$ 754										$ 754	$ 754	$ 724
Transfer of warrant to capital stock upon excise of cashless warrant	232		232
Difference in repurchase charge to retained earnings	30
Repurchase Price	$ 9.782												$ 9.782
issued price of share repurchased													$ 9.39
Shares Repurchased	77,071												77,071	77,071
Shares of common stock issued		266,568	12,268,443	11,681,051		500,000
Warrants exercised	105,000		105,000	266,568				191,199	191,199	100,000	75,369	346,000	105,000
Increase in common stock due to exercise of warrants		1,554
Cash received upon exercise of warrants		1,095		1,096
Value of exercised warrants determined upon issuance		459
Stock issued in connection with asset purchase - Shares							29,112
Stock issued in connection with asset purchase - Value			$ 200				$ 200