Stockholders' Equity - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended											12 Months Ended								0 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2014 Discontinued Operations	Jul. 31, 2013 Discontinued Operations	Jul. 31, 2012 Discontinued Operations	Jul. 31, 2013 Cashless Exercise	Jul. 31, 2014 Minimum	Jul. 31, 2014 Maximum	Jul. 31, 2014 2010 Equity Incentive Plan	Jul. 31, 2014 2006 Equity Incentive Plan	Jul. 31, 2014 Restricted Stock Units (RSUs)	Jul. 31, 2013 Restricted Stock Units (RSUs)	Jul. 31, 2014 Stock Option Awards	Jul. 31, 2013 Stock Option Awards	Jul. 31, 2012 Stock Option Awards	Jul. 31, 2014 Restricted Stock Awards	Jul. 31, 2013 Restricted Stock Awards	Jul. 31, 2012 Restricted Stock Awards	Aug. 31, 2011 August 2011 Repurchase Agreement	Jan. 20, 2012 January 2012 Repurchase Agreement	Jan. 18, 2012 January 2012 Repurchase Agreement	Jan. 20, 2012 Catterton Repurchase Agreements	Jan. 18, 2012 Catterton Repurchase Agreements
Stock Based Compensation And Stockholders Equity [Line Items]
Common stock purchased, shares																				1,000,000	1,000,000		1,000,000
Common stock price per share																				$ 20.00	$ 28.50		$ 28.50
Aggregate purchase price of common stock			$ 77,000																	$ 20,000	$ 28,500		$ 28,500
Closing price of common stock																				$ 20.62		$ 29.34		$ 29.34
Percentage of issued and outstanding common stock prior to repurchase																				1.80%	1.80%		1.80%
Number of shares authorized under stock option plan										2,000,000	1,100,000
Number of shares available to be granted										1,556,224	30,000
Option expiration from the date of grant, in years	10 years
Option vesting period								3 years	5 years								5 years
Weighted average remaining contractual life of outstanding options, years	9 months
Weighted average remaining contractual life of exercisable options, years	9 months
Options granted during the period	0	0	0
Total compensation expenses				480	207	0						5,140	2,290	0	393	645	91	133	43
Cash received from stock option exercises	3,206	5,845	1,428
Total intrinsic value of stock options exercised	2,597	7,502	931
Stock option exercised	101,313	498,412	80,500				314,000
Stock option value exercised	3,206	14,267
Share issued during period							63,464
Tax withholding paid on behalf Of employees		2,009
Unrecognized compensation costs																	331
Weighted average recognition period for compensation expenses, years																	2 years 11 months 19 days
Stock-based compensation	5,231	2,816	688
Tax benefits from stock compensation expense	$ 1,925	$ 1,032	$ 239