Acquisition of Kantar Media's U.S. Based Television Measurement Assets - Pro Forma (Details) (RPD Business [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
RPD Business [Member]
Business Acquisition, Pro Forma Information [Abstract]
Total revenue	$ 28,322	$ 21,195	$ 80,253	$ 59,077
Net loss attributable to Rentrak Corporation	$ (1,868)	$ (1)	$ (1,952)	$ (982)
Basic earnings per share (usd per share)	$ (0.12)	$ 0.00	$ (0.13)	$ (0.07)
Diluted earnings per share (usd per share)	$ (0.12)	$ 0.00	$ (0.12)	$ (0.07)

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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