Redeemable Preferred Stock - Additional Information (Detail)	9 Months Ended	12 Months Ended	1 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Oct. 18, 2013 Subsequent Event [Member]
Common Stock And Preferred Stock [Line Items]
Preferred stock dividend rate, percentage	7.00%	7.00%
Conversion of preferred stock			810,382
Basis of conversion of preferred stock			7% preferred stock will be converted at the rate of 4.34164 shares of the Company's common stock for each share of 7% preferred stock, or into an aggregate of 3,518,386 shares of common stock.
Convertible preferred stock issued upon conversion			4.34164
Conversion of shares issued			3,518,386