The Company	9 Months Ended
Mar. 31, 2019
Organization [Abstract]
The Company	1. The Company QuinStreet, Inc. (the “Company”) is a leader in performance marketplace products and technologies. The Company was incorporated in California in April 1999 and reincorporated in Delaware in December 2009. The Company specializes in customer acquisition for clients in high value, information-intensive markets or “verticals,” including financial services, education, home services and business-to-business technology. The corporate headquarters are located in Foster City, California, with additional offices throughout the United States, Brazil and India. While the majority of the Company’s operations and revenue are in North America, the Company has emerging businesses in Brazil and India.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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