Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiary (Detail) - Condensed Consolidating Balance Sheets (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	May 31, 2012	Nov. 30, 2011	Aug. 19, 2011	May 31, 2011
CURRENT ASSETS:
Cash and cash equivalents	$ 19,013	$ 18,578	$ 36,875	$ 322,963	$ 302,603
Accounts receivable, net	60,731	66,392
Inventories	36,761	33,370
Deferred income tax assets, current portion	5,634	5,489
Prepaid expenses and other current assets	11,087	11,738
Total current assets	133,226	135,567
PROPERTY AND EQUIPMENT, Net	64,488	64,662
GOODWILL	968,521	966,338
INTANGIBLE ASSETS, Net	712,254	735,522
DEFERRED FINANCING COSTS	34,955	38,769
OTHER ASSETS	8,340	8,295
Total assets	1,921,784	1,949,153
CURRENT LIABILITIES:
Accounts payable	14,328	12,734
Income taxes payable	3,762	3,654
Deferred revenue, current portion	2,476	2,606
Current portion of long term debt, net of debt discounts	5,108	3,922
Total current liabilities	62,790	64,272
LONG TERM DEBT, NET OF DEBT DISCOUNTS	987,070	986,361
DEFERRED REVENUE	335	431
DEFERRED INCOME TAX LIABILITIES	232,778	245,496
OTHER LONG-TERM LIABILITIES	15,923	15,215
Total liabilities	1,298,896	1,311,775
SHAREHOLDERS' EQUITY:
Total shareholders’ equity	622,888	637,378
Total liabilities and shareholders’ equity	1,921,784	1,949,153
Immucor Inc [Member]
CURRENT ASSETS:
Cash and cash equivalents	1,146	8,093
Accounts receivable, net	26,836	27,542
Intercompany receivable	49,042	46,856
Inventories	23,828	21,697
Deferred income tax assets, current portion	4,168	4,168
Prepaid expenses and other current assets	5,302	6,336
Total current assets	110,322	114,692
PROPERTY AND EQUIPMENT, Net	42,220	44,103
INVESTMENT IN SUBSIDIARIES	171,300	162,895
GOODWILL	903,512	903,512
INTANGIBLE ASSETS, Net	658,559	682,187
DEFERRED FINANCING COSTS	34,955	38,769
OTHER ASSETS	7,816	7,817
Total assets	1,928,684	1,953,975
CURRENT LIABILITIES:
Accounts payable	10,295	9,816
Intercompany payable	918	190
Accrued expenses and other current liabilities	27,963	31,250
Income taxes payable	30,724	30,719
Deferred revenue, current portion	1,338	1,270
Current portion of long term debt, net of debt discounts	5,108	3,922
Total current liabilities	76,346	77,167
LONG TERM DEBT, NET OF DEBT DISCOUNTS	987,070	986,361
DEFERRED REVENUE	312	391
DEFERRED INCOME TAX LIABILITIES	227,324	238,582
OTHER LONG-TERM LIABILITIES	14,744	14,096
Total liabilities	1,305,796	1,316,597
SHAREHOLDERS' EQUITY:
Total shareholders’ equity	622,888	637,378
Total liabilities and shareholders’ equity	1,928,684	1,953,975
Guarantor [Member]
CURRENT ASSETS:
Accounts receivable, net	605	489
Intercompany receivable	78	23
Inventories	2,174	1,438
Deferred income tax assets, current portion	531	531
Prepaid expenses and other current assets	31,353	31,227
Total current assets	34,741	33,708
PROPERTY AND EQUIPMENT, Net	2,841	1,407
GOODWILL	6,659	6,659
INTANGIBLE ASSETS, Net	10,330	10,438
OTHER ASSETS	7,125	5,558
Total assets	61,696	57,770
CURRENT LIABILITIES:
Accounts payable	1,271	1,145
Intercompany payable	45,798	39,177
Accrued expenses and other current liabilities	1,198	1,421
Deferred revenue, current portion	17	20
Total current liabilities	48,284	41,763
Total liabilities	48,284	41,763
SHAREHOLDERS' EQUITY:
Total shareholders’ equity	13,412	16,007
Total liabilities and shareholders’ equity	61,696	57,770
Non-Guarantors [Member]
CURRENT ASSETS:
Cash and cash equivalents	17,960	10,629
Accounts receivable, net	33,290	38,361
Intercompany receivable	3,748	7,610
Inventories	10,759	10,235
Deferred income tax assets, current portion	935	790
Prepaid expenses and other current assets	5,041	4,784
Total current assets	71,733	72,409
PROPERTY AND EQUIPMENT, Net	19,427	19,152
INVESTMENT IN SUBSIDIARIES	4	4
GOODWILL	58,350	56,167
INTANGIBLE ASSETS, Net	43,365	42,897
OTHER ASSETS	415	370
Total assets	193,294	190,999
CURRENT LIABILITIES:
Accounts payable	2,762	1,773
Intercompany payable	6,152	15,122
Accrued expenses and other current liabilities	8,048	8,829
Income taxes payable	3,647	3,544
Deferred revenue, current portion	1,121	1,316
Total current liabilities	21,730	30,584
DEFERRED REVENUE	23	40
DEFERRED INCOME TAX LIABILITIES	12,470	12,364
OTHER LONG-TERM LIABILITIES	1,179	1,119
Total liabilities	35,402	44,107
SHAREHOLDERS' EQUITY:
Total shareholders’ equity	157,892	146,892
Total liabilities and shareholders’ equity	193,294	190,999
Intersegment Elimination [Member]
CURRENT ASSETS:
Cash and cash equivalents	(93)	(144)
Intercompany receivable	(52,868)	(54,489)
Prepaid expenses and other current assets	(30,609)	(30,609)
Total current assets	(83,570)	(85,242)
INVESTMENT IN SUBSIDIARIES	(171,304)	(162,899)
OTHER ASSETS	(7,016)	(5,450)
Total assets	(261,890)	(253,591)
CURRENT LIABILITIES:
Intercompany payable	(52,868)	(54,489)
Accrued expenses and other current liabilities	(93)	(144)
Income taxes payable	(30,609)	(30,609)
Total current liabilities	(83,570)	(85,242)
DEFERRED INCOME TAX LIABILITIES	(7,016)	(5,450)
Total liabilities	(90,586)	(90,692)
SHAREHOLDERS' EQUITY:
Total shareholders’ equity	(171,304)	(162,899)
Total liabilities and shareholders’ equity	(261,890)	(253,591)
Total [Member]
CURRENT ASSETS:
Cash and cash equivalents	19,013	18,578
Accounts receivable, net	60,731	66,392
Inventories	36,761	33,370
Deferred income tax assets, current portion	5,634	5,489
Prepaid expenses and other current assets	11,087	11,738
Total current assets	133,226	135,567
PROPERTY AND EQUIPMENT, Net	64,488	64,662
GOODWILL	968,521	966,338
INTANGIBLE ASSETS, Net	712,254	735,522
DEFERRED FINANCING COSTS	34,955	38,769
OTHER ASSETS	8,340	8,295
Total assets	1,921,784	1,949,153
CURRENT LIABILITIES:
Accounts payable	14,328	12,734
Accrued expenses and other current liabilities	37,116	41,356
Income taxes payable	3,762	3,654
Deferred revenue, current portion	2,476	2,606
Current portion of long term debt, net of debt discounts	5,108	3,922
Total current liabilities	62,790	64,272
LONG TERM DEBT, NET OF DEBT DISCOUNTS	987,070	986,361
DEFERRED REVENUE	335	431
DEFERRED INCOME TAX LIABILITIES	232,778	245,496
OTHER LONG-TERM LIABILITIES	15,923	15,215
Total liabilities	1,298,896	1,311,775
SHAREHOLDERS' EQUITY:
Total shareholders’ equity	622,888	637,378
Total liabilities and shareholders’ equity	$ 1,921,784	$ 1,949,153