Treasury Stock - Additional Information (Detail) - shares	1 Months Ended	3 Months Ended
	Apr. 30, 2013	Jan. 31, 2015
Equity, Class of Treasury Stock [Line Items]
Shares purchased under repurchase program	1,000,000
Number of shares of common stock repurchased		0
Maximum [Member]
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to repurchase	1,000,000	1,000,000