Preferred Stock Subject to Mandatory Redemption - Additional Information (Detail) (USD $)	12 Months Ended		3 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2013	Aug. 31, 2012 Series A Preferred Stock [Member]	Aug. 31, 2012 Series A Preferred Stock [Member]	Aug. 31, 2012 Series B Preferred Stock [Member]	Apr. 07, 2010 Series A Cumulative Non-Voting Non-Convertible Preferred Stock, Redeemable [Member]	Aug. 31, 2012 Series A Cumulative Non-Voting Non-Convertible Preferred Stock, Redeemable [Member]	Apr. 07, 2010 Series B Voting Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock issued value						$ 40,000,000		$ 7,700,000
Dividend on preferred stock (in percentage)						15.00%	6.00%
Preferred stock, shares issued (in shares)		0						100,000
Preferred Stock, shares authorized (in shares)		1,000,000
Preferred stock, shares par value (in USD per share)		$ 1.00
Preferred stock, shares outstanding (in shares)		0
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Fair Value of Shares						32,300,000
Amortization period of the discount on the Series A mandatory redeemable preferred stock (in years)							7 years
Preferred stock dividends accrued as a percentage of outstanding Preferred Stock							9.00%
Preferred stock, redeemed	40,000,000			48,900,000
Preferred stock, redeemed shares				100,000
Preferred stock redemption price			23,500,000	40,000,000
Accrued dividend			5,400,000	8,900,000
Accelerated discount accretion			3,200,000	5,500,000
Amortization of issuance costs				$ 1,100,000
Preferred stock, converted					100,000
Common stock, Converted shares					1,000,000