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Name:	pets_StockholdersEquityNoteLineItems
Namespace Prefix:	pets_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Shareholders' Equity (Detail Textuals 1) - Share Repurchase Plan - USD ($) $ in Millions	Mar. 31, 2017	Aug. 01, 2011	Nov. 01, 2010	Oct. 31, 2008	Nov. 08, 2006
Stockholders Equity Note [Line Items]
Amount approved of share repurchase plan		$ 20.0	$ 20.0	$ 20.0	$ 20.0
Value of remaining shares	$ 10.2