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      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
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  </MyReports>
  <Logs>
    <Log type="Info">Element us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity had a mix of decimals attribute values: -6 -5.</Log>
    <Log type="Info">'Monetary' elements on report '139 - Disclosure - Intangibles Assets, Net and Goodwill - Additional Information (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 103 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2011'</Log>
    <Log type="Info">Process Flow-Through: 104 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 105 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS</Log>
    <Log type="Info">Process Flow-Through: 106 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 107 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME</Log>
    <Log type="Info">Process Flow-Through: 108 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS</Log>
  </Logs>
  <InputFiles>
    <File>qnst-20121231.xml</File>
    <File>qnst-20121231.xsd</File>
    <File>qnst-20121231_cal.xml</File>
    <File>qnst-20121231_def.xml</File>
    <File>qnst-20121231_lab.xml</File>
    <File>qnst-20121231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
