Classification of Stock Based Compensation Expense (Parenthetical) (Detail)	Jun. 30, 2012	Jun. 30, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs
Recognized tax benefit related to share-based compensation expense	39.20%	38.70%

Employee service share-based compensation, tax benefit from compensation expense, percentage

No definition available.

Name:	qsft_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpensePercentage
Namespace Prefix:	qsft_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant