Note 2 - Business Combinations (Details) - Sources and Uses of Funds in Connection with Acquisition (USD $) In Thousands, unless otherwise specified	12 Months Ended	0 Months Ended
	May 31, 2013	Mar. 22, 2013 Including Transaction Costs and Additional Working Capital [Member] LIFECODES [Member]	Aug. 19, 2011 Including Transaction Costs [Member] Immucor Inc [Member]	Mar. 22, 2013 LIFECODES [Member]	Aug. 19, 2011 Immucor Inc [Member]
Sources:
Proceeds from Term Loan	$ 338,076			$ 50,000	$ 596,550
Proceeds from Notes					394,856
Proceeds from equity contributions	42,500			42,500	735,187
Company cash used in transaction					301,053
Proceeds from business acquisition				92,500	2,027,646
Uses:
Equity purchase price				86,204	1,939,387
Transaction costs				4,161	88,259
Additional working capital				2,135
Payments to acquire business		$ 92,500	$ 2,027,646	$ 90,604	$ 1,939,387