Note 21 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended	9 Months Ended			12 Months Ended		9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2012	Aug. 19, 2011	Feb. 29, 2012	May 31, 2012	May 31, 2012	May 31, 2012	May 31, 2013	May 31, 2011	May 31, 2012 Successor [Member] Immucor Inc [Member]	May 31, 2013 Successor [Member] Immucor Inc [Member]	May 31, 2012 Successor [Member] Guarantor [Member]	May 31, 2013 Successor [Member] Guarantor [Member]	May 31, 2012 Successor [Member] Non-Guarantors [Member]	May 31, 2013 Successor [Member] Non-Guarantors [Member]	May 31, 2012 Successor [Member] Eliminations [Member]	May 31, 2013 Successor [Member] Eliminations [Member]	May 31, 2012 Successor [Member] Total [Member]	May 31, 2013 Successor [Member] Total [Member]	May 31, 2012 Successor [Member]	May 31, 2013 Successor [Member]	May 31, 2012 Successor [Member]	Aug. 19, 2011 Predecessor [Member] Immucor Inc [Member]	May 31, 2011 Predecessor [Member] Immucor Inc [Member]	Aug. 19, 2011 Predecessor [Member] Guarantor [Member]	May 31, 2011 Predecessor [Member] Guarantor [Member]	Aug. 19, 2011 Predecessor [Member] Non-Guarantors [Member]	May 31, 2011 Predecessor [Member] Non-Guarantors [Member]	Aug. 19, 2011 Predecessor [Member] Eliminations [Member]	May 31, 2011 Predecessor [Member] Eliminations [Member]	Aug. 19, 2011 Predecessor [Member] Total [Member]	May 31, 2011 Predecessor [Member] Total [Member]	Aug. 19, 2011 Predecessor [Member]	May 31, 2012 Predecessor [Member]	May 31, 2011 Predecessor [Member]
Note 21 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES		$ 74,910		$ 261,814	$ 261,814		$ 347,788	$ 333,091	$ 195,377	$ 256,676	$ 4,087	$ 15,835	$ 97,528	$ 124,465	$ (35,178)	$ (49,188)	$ 261,814	$ 347,788			$ 261,814	$ 55,063	$ 244,339	$ 980	$ 4,577	$ 26,648	$ 116,748	$ (7,781)	$ (32,573)	$ 74,910	$ 333,091		$ 74,910
COST OF SALES (exclusive of amortization shown separately below)		22,955		105,698			120,027	96,175	73,109	84,320	3,844	11,056	63,923	73,839	(35,178)	(49,188)	105,698	120,027				17,070	67,726	722	3,549	12,944	57,473	(7,781)	(32,573)	22,955	96,175
GROSS MARGIN		51,955		156,116			227,761	236,916	122,268	172,356	243	4,779	33,605	50,626			156,116	227,761			156,116	37,993	176,613	258	1,028	13,704	59,275			51,955	236,916		51,955
OPERATING EXPENSES:
Research and development		4,895		13,929			21,313	15,900	7,724	13,428	6,113	7,850	92	35			13,929	21,313				2,390	6,815	2,471	8,925	34	160			4,895	15,900
Selling and marketing		10,510		32,913			50,129	36,431	17,868	25,611	1,654	3,632	13,391	20,886			32,913	50,129				5,321	17,265	568	1,919	4,621	17,247			10,510	36,431
Distribution		3,952		14,333			18,718	16,508	8,697	11,599	137	421	5,499	6,698			14,333	18,718			14,300	2,331	9,932	34	130	1,587	6,446			3,952	16,508		4,000
General and administrative		19,312		36,954			42,801	37,247	26,850	32,259	1,682	6,673	9,784	9,985			38,316	48,917				33,903	24,899	657	2,892	3,615	9,956			38,175	37,747
Amortization of intangibles		931		39,224			50,765	4,333	37,173	47,820	161	663	1,890	2,282			39,224	50,765				117	539	757	3,544	57	250			931	4,333
Certain litigation expenses	22,000			22,000					22,000								22,000
Loss on disposition of fixed assets		135				417	1,306	1,072		1,175								1,175
Total operating expenses		58,463		160,715			191,017	110,919	120,312	131,892	9,747	19,239	30,656	39,886			160,715	191,017				44,062	59,450	4,487	17,410	9,914	34,059			58,463	110,919
(LOSS) INCOME FROM OPERATIONS		(6,508)		(4,599)			36,744	125,997	1,956	40,464	(9,504)	(14,460)	2,949	10,740			(4,599)	36,744			(4,599)	(6,069)	117,163	(4,229)	(16,382)	3,790	25,216			(6,508)	125,997		(6,508)
NON-OPERATING (EXPENSE) INCOME:
Interest income		142		7			28	706					89	97	(82)	(69)	7	28				46	279			117	527	(21)	(100)	142	706
Interest expense				(77,048)		(77,048)	(90,830)	(70)	(77,066)	(90,875)		(2)	(64)	(22)	82	69	(77,048)	(90,830)					(56)			(21)	(114)	21	100		(70)
Loss on extinguishment of debt							(9,111)			(9,111)								(9,111)
Other, net		2,673		447			(539)	3,997	406	(1,043)		(84)	41	588			447	(539)				(246)	(103)	14	4,168	2,905	(68)			2,673	3,997
Total non-operating (expense) income		2,815		(76,594)			(100,452)	4,633	(76,660)	(101,029)		(86)	66	663			(76,594)	(100,452)				(200)	120	14	4,168	3,001	345			2,815	4,633
(LOSS) INCOME BEFORE INCOME TAXES		(3,693)		(81,193)		(81,193)	(63,708)	130,630	(74,704)	(60,565)	(9,504)	(14,546)	3,015	11,403			(81,193)	(63,708)				(6,269)	117,283	(4,215)	(12,214)	6,791	25,561			(3,693)	130,630
(BENEFIT) PROVISION FOR INCOME TAXES		2,681		(31,546)		(31,546)	(24,566)	41,303	(29,426)	(23,783)	(3,275)	(4,773)	1,155	3,990			(31,546)	(24,566)				1,497	42,051	(1,598)	(8,721)	2,782	7,973			2,681	41,303
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES		(6,374)		(49,647)		(49,647)	(39,142)	89,327	(45,278)	(36,782)	(6,229)	(9,773)	1,860	7,413			(49,647)	(39,142)			(49,647)	(7,766)	75,232	(2,617)	(3,493)	4,009	17,588			(6,374)	89,327		(6,374)
Net (Loss) Income of consolidated subsidiaries									(4,369)	(2,360)					4,369	2,360						1,392	14,095					(1,392)	(14,095)
NET (LOSS) INCOME		$ (6,374)	$ (49,647)				$ (39,142)	$ 89,327	$ (49,647)	$ (39,142)	$ (6,229)	$ (9,773)	$ 1,860	$ 7,413	$ 4,369	$ 2,360	$ (49,647)	$ (39,142)	$ (49,647)	$ (39,142)		$ (6,374)	$ 89,327	$ (2,617)	$ (3,493)	$ 4,009	$ 17,588	$ (1,392)	$ (14,095)	$ (6,374)	$ 89,327	$ (6,374)		$ 89,327