Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Aug. 31, 2013	Aug. 31, 2012
Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES	$ 96,044	$ 85,154
COST OF SALES (exclusive of amortization shown separately below)	36,051	27,101
GROSS MARGIN	59,993	58,053
OPERATING EXPENSES:
Research and development	8,130	4,885
Selling and marketing	14,292	12,221
Distribution	4,719	4,508
General and administrative	10,975	10,116
Amortization of intangibles	13,207	12,381
Acquisition-related item	(1,320)
Total operating expenses	50,003	44,111
(LOSS) INCOME FROM OPERATIONS	9,990	13,942
NON-OPERATING INCOME (EXPENSE):
Interest income	9	3
Interest expense	(22,178)	(24,488)
Loss on extinguishment of debt		(6,686)
Other, net	(216)	120
Total non-operating (expense) income	(22,385)	(31,051)
(LOSS) INCOME BEFORE INCOME TAXES	(12,395)	(17,109)
(BENEFIT) PROVISION FOR INCOME TAXES	(4,635)	(6,474)
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES	(7,760)	(10,635)
NET (LOSS) INCOME	(7,760)	(10,635)
Immucor Inc [Member]
Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES	64,210	64,505
COST OF SALES (exclusive of amortization shown separately below)	22,026	20,027
GROSS MARGIN	42,184	44,478
OPERATING EXPENSES:
Research and development	3,632	3,208
Selling and marketing	6,327	6,958
Distribution	2,722	2,875
General and administrative	6,865	7,550
Amortization of intangibles	11,971	11,771
Acquisition-related item	(1,320)
Total operating expenses	30,197	32,362
(LOSS) INCOME FROM OPERATIONS	11,987	12,116
NON-OPERATING INCOME (EXPENSE):
Interest income	1
Interest expense	(22,191)	(24,488)
Loss on extinguishment of debt		(6,686)
Other, net	(389)	(23)
Total non-operating (expense) income	(21,801)	(31,197)
(LOSS) INCOME BEFORE INCOME TAXES	(9,814)	(19,081)
(BENEFIT) PROVISION FOR INCOME TAXES	(3,681)	(7,085)
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES	(6,133)	(11,996)
Net (Loss) Income of consolidated subsidiaries	(1,105)	1,361
NET (LOSS) INCOME	(7,238)	(10,635)
Guarantor [Member]
Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES	13,664	1,441
COST OF SALES (exclusive of amortization shown separately below)	9,144	917
GROSS MARGIN	4,520	524
OPERATING EXPENSES:
Research and development	4,490	1,643
Selling and marketing	2,093	460
Distribution	382	43
General and administrative	1,736	474
Amortization of intangibles	668	54
Total operating expenses	9,369	2,674
(LOSS) INCOME FROM OPERATIONS	(4,849)	(2,150)
NON-OPERATING INCOME (EXPENSE):
Interest income	1
Other, net	28
Total non-operating (expense) income	29
(LOSS) INCOME BEFORE INCOME TAXES	(4,820)	(2,150)
(BENEFIT) PROVISION FOR INCOME TAXES	(1,616)	(712)
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES	(3,204)	(1,438)
NET (LOSS) INCOME	(3,204)	(1,438)
Non-Guarantors [Member]
Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES	34,991	29,605
COST OF SALES (exclusive of amortization shown separately below)	21,702	16,554
GROSS MARGIN	13,289	13,051
OPERATING EXPENSES:
Research and development	8	34
Selling and marketing	5,872	4,803
Distribution	1,615	1,590
General and administrative	2,374	2,092
Amortization of intangibles	568	556
Total operating expenses	10,437	9,075
(LOSS) INCOME FROM OPERATIONS	2,852	3,976
NON-OPERATING INCOME (EXPENSE):
Interest income	28	11
Interest expense	(8)	(8)
Other, net	152	143
Total non-operating (expense) income	172	146
(LOSS) INCOME BEFORE INCOME TAXES	3,024	4,122
(BENEFIT) PROVISION FOR INCOME TAXES	925	1,323
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES	2,099	2,799
NET (LOSS) INCOME	2,099	2,799
Eliminations [Member]
Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES	(16,821)	(10,397)
COST OF SALES (exclusive of amortization shown separately below)	(16,821)	(10,397)
NON-OPERATING INCOME (EXPENSE):
Interest income	(21)	(8)
Interest expense	21	8
Other, net	(785)
Total non-operating (expense) income	(785)
(LOSS) INCOME BEFORE INCOME TAXES	(785)
(BENEFIT) PROVISION FOR INCOME TAXES	(263)
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES	(522)
Net (Loss) Income of consolidated subsidiaries	1,105	(1,361)
NET (LOSS) INCOME	583	(1,361)
Total [Member]
Note 16 - Condensed Consolidating Financial Information Of Guarantor Subsidiaries (Details) - Condensed Consolidating Statements of Operations [Line Items]
NET SALES	96,044	85,154
COST OF SALES (exclusive of amortization shown separately below)	36,051	27,101
GROSS MARGIN	59,993	58,053
OPERATING EXPENSES:
Research and development	8,130	4,885
Selling and marketing	14,292	12,221
Distribution	4,719	4,508
General and administrative	10,975	10,116
Amortization of intangibles	13,207	12,381
Acquisition-related item	(1,320)
Total operating expenses	50,003	44,111
(LOSS) INCOME FROM OPERATIONS	9,990	13,942
NON-OPERATING INCOME (EXPENSE):
Interest income	9	3
Interest expense	(22,178)	(24,488)
Loss on extinguishment of debt		(6,686)
Other, net	(216)	120
Total non-operating (expense) income	(22,385)	(31,051)
(LOSS) INCOME BEFORE INCOME TAXES	(12,395)	(17,109)
(BENEFIT) PROVISION FOR INCOME TAXES	(4,635)	(6,474)
NET (LOSS) INCOME BEFORE EARNINGS OF CONSOLIDATED SUBSIDIARIES	(7,760)	(10,635)
NET (LOSS) INCOME	$ (7,760)	$ (10,635)