Acquisitions - Aggregate Purchase Price Recorded - CarInsurance.com (Detail) (CarInsurance.com [Member], USD $) In Thousands, unless otherwise specified	Nov. 05, 2010
CarInsurance.com [Member]
Acquisitions [Line Items]
Cash	$ 49,655

Business Acquisition Cost Of Acquired Entity Cash Paid Net

No definition available.

Name:	qnst_BusinessAcquisitionCostOfAcquiredEntityCashPaidNet
Namespace Prefix:	qnst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant