Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended	1 Months Ended
Nov. 23, 2011	Aug. 31, 2012
Commitments and Contingencies
Amount of damages awarded for pre-verdict infringement	$ 1,018
Amount of damages received for pre-verdict infringement		$ 1,018

Amount of damages awarded to the plaintiff in the legal matter.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14435-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14557-108349

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration