Note 2 - Business Combinations (Details) - Summarized Results of Operations (Pro Forma) (USD $) In Thousands, unless otherwise specified	12 Months Ended
May 31, 2012	May 31, 2011	May 31, 2013 Lifecodes Acquisition [Member]	May 31, 2012 Lifecodes Acquisition [Member]
Note 2 - Business Combinations (Details) - Summarized Results of Operations (Pro Forma) [Line Items]
Revenue	$ 336,724	$ 333,091	$ 385,916	$ 382,368
Net loss	$ (55,140)	$ (3,858)	$ (39,326)	$ (61,121)

The pro forma net Income or Loss for the 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration