Note 4 - Inventories (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
May 31, 2013 Cost of Sales [Member] LIFECODES [Member]	Aug. 19, 2011 Immucor Inc [Member]	Mar. 22, 2013 LIFECODES [Member]
Note 4 - Inventories (Details) [Line Items]
Inventory Adjustments		$ 24.4	$ 4.5
Inventory Write-down	$ 1.7

Certain changes made in the current period to the value and amount of inventory reported.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph b

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=28360613&loc=d3e4492-108314

Name:	us-gaap_InventoryAdjustments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant