Earnings Per Share - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended		5 Months Ended	18 Months Ended
	Apr. 30, 2013	Oct. 25, 2011	Sep. 30, 2013	Apr. 25, 2013
Earnings Per Share [Line Items]
Stock repurchase program, authorized amount	$ 200,000	$ 250,000
Shares repurchased under repurchase program			12,376,240	13,986,349
Shares repurchased average price per share			$ 4.89	$ 7.67
Shares repurchased under repurchase program, value			$ 60,535
Maximum
Earnings Per Share [Line Items]
Stock repurchase program, expiration date	Apr. 30, 2015	Apr. 25, 2013