Guarantor and Non-Guarantor Financial Statements - Schedule of Condensed Statements of Operations and Comprehensive Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2014	Nov. 30, 2013	Nov. 30, 2014	Nov. 30, 2013
Schedule Of Condensed Statements Of Operations [Line Items]
Net sales	$ 843.6us-gaap_SalesRevenueNet	$ 825.7us-gaap_SalesRevenueNet	$ 1,618.4us-gaap_SalesRevenueNet	$ 1,556.4us-gaap_SalesRevenueNet
Cost of sales	183.8us-gaap_CostOfRevenue	255.1us-gaap_CostOfRevenue	399.7us-gaap_CostOfRevenue	463.1us-gaap_CostOfRevenue
Gross profit	659.8us-gaap_GrossProfit	570.6us-gaap_GrossProfit	1,218.7us-gaap_GrossProfit	1,093.3us-gaap_GrossProfit
Selling, general and administrative expense	367.7	340.4	729.4	653.7
Research and development expense	42.9us-gaap_ResearchAndDevelopmentExpense	41.4us-gaap_ResearchAndDevelopmentExpense	85.7us-gaap_ResearchAndDevelopmentExpense	78.9us-gaap_ResearchAndDevelopmentExpense
Amortization	79.6us-gaap_AmortizationOfIntangibleAssets	75.2us-gaap_AmortizationOfIntangibleAssets	151.5us-gaap_AmortizationOfIntangibleAssets	150.7us-gaap_AmortizationOfIntangibleAssets
Operating income	169.6us-gaap_OperatingIncomeLoss	113.6us-gaap_OperatingIncomeLoss	252.1us-gaap_OperatingIncomeLoss	210.0us-gaap_OperatingIncomeLoss
Interest expense	78.5us-gaap_InterestExpense	105.7us-gaap_InterestExpense	158.6us-gaap_InterestExpense	193.3us-gaap_InterestExpense
Other (income) expense	(2.1)us-gaap_OtherNonoperatingIncomeExpense	3.7us-gaap_OtherNonoperatingIncomeExpense	(6.3)us-gaap_OtherNonoperatingIncomeExpense	5.9us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	93.2	4.2	99.8	10.8
Net income	89.8us-gaap_NetIncomeLoss	4.9us-gaap_NetIncomeLoss	97.1us-gaap_NetIncomeLoss	36.0us-gaap_NetIncomeLoss
Other comprehensive income (loss)	(136.1)	37.1	(180.3)	55.3
Comprehensive income (loss)	(46.3)us-gaap_ComprehensiveIncomeNetOfTax	42.0us-gaap_ComprehensiveIncomeNetOfTax	(83.2)us-gaap_ComprehensiveIncomeNetOfTax	91.3us-gaap_ComprehensiveIncomeNetOfTax
Biomet, Inc [Member]
Schedule Of Condensed Statements Of Operations [Line Items]
Net sales	0	0	0	0
Cost of sales	0	0	0	0
Gross profit	0	0	0	0
Selling, general and administrative expense	0	0	0	0
Research and development expense	0	0	0	0
Amortization	0	0	0	0
Operating income	0	0	0	0
Interest expense	78.5	106.1	158.6	193.1
Other (income) expense	0	4.8	0	4.8
Income before income taxes	(78.5)	(110.9)	(158.6)	(197.9)
Tax expense (benefit)	(29.8)	(42.1)	(60.3)	(75.2)
Equity in earnings of subsidiaries	138.5	73.7	195.4	158.7
Net income	89.8	4.9	97.1	36.0
Other comprehensive income (loss)	(136.1)	8.8	(180.3)	22.3
Comprehensive income (loss)	(46.3)	13.7	(83.2)	58.3
Guarantor [Member]
Schedule Of Condensed Statements Of Operations [Line Items]
Net sales	532.5	510.6	1,041.3	992.0
Cost of sales	158.5	221.5	364.7	402.2
Gross profit	374.0	289.1	676.6	589.8
Selling, general and administrative expense	238.5	209.6	469.7	403.5
Research and development expense	32.0	30.3	63.4	58.2
Amortization	60.6	61.8	116.1	123.1
Operating income	42.9	(12.6)	27.4	5.0
Interest expense	0	0	0	0
Other (income) expense	5.9	(1.2)	11.1	(3.5)
Income before income taxes	37.0	(11.4)	16.3	8.5
Tax expense (benefit)	14.0	(4.3)	6.1	3.3
Equity in earnings of subsidiaries	0	0	0	0
Net income	23.0	(7.1)	10.2	5.2
Other comprehensive income (loss)	0	0	0.1	0
Comprehensive income (loss)	23.0	(7.1)	10.3	5.2
Non-Guarantors [Member]
Schedule Of Condensed Statements Of Operations [Line Items]
Net sales	311.1	315.1	577.1	564.4
Cost of sales	25.3	33.6	35.0	60.9
Gross profit	285.8	281.5	542.1	503.5
Selling, general and administrative expense	129.2	130.8	259.7	250.2
Research and development expense	10.9	11.1	22.3	20.7
Amortization	19.0	13.4	35.4	27.6
Operating income	126.7	126.2	224.7	205.0
Interest expense	0	(0.4)	0	0.2
Other (income) expense	(8.0)	0.1	(17.4)	4.6
Income before income taxes	134.7	126.5	242.1	200.2
Tax expense (benefit)	19.2	45.7	56.9	46.7
Equity in earnings of subsidiaries	0	0	0	0
Net income	115.5	80.8	185.2	153.5
Other comprehensive income (loss)	(135.7)	28.3	(183.6)	33.0
Comprehensive income (loss)	(20.2)	109.1	1.6	186.5
Eliminations [Member]
Schedule Of Condensed Statements Of Operations [Line Items]
Net sales	0	0	0	0
Cost of sales	0	0	0	0
Gross profit	0	0	0	0
Selling, general and administrative expense	0	0	0	0
Research and development expense	0	0	0	0
Amortization	0	0	0	0
Operating income	0	0	0	0
Interest expense	0	0	0	0
Other (income) expense	0	0	0	0
Income before income taxes	0	0	0	0
Tax expense (benefit)	0	0	0	0
Equity in earnings of subsidiaries	(138.5)	(73.7)	(195.4)	(158.7)
Net income	(138.5)	(73.7)	(195.4)	(158.7)
Other comprehensive income (loss)	135.7	0	183.5	0
Comprehensive income (loss)	(2.8)	(73.7)	(11.9)	(158.7)
Biomet, Inc. [Member]
Schedule Of Condensed Statements Of Operations [Line Items]
Net sales	843.6	825.7	1,618.4	1,556.4
Cost of sales	183.8	255.1	399.7	463.1
Gross profit	659.8	570.6	1,218.7	1,093.3
Selling, general and administrative expense	367.7	340.4	729.4	653.7
Research and development expense	42.9	41.4	85.7	78.9
Amortization	79.6	75.2	151.5	150.7
Operating income	169.6	113.6	252.1	210.0
Interest expense	78.5	105.7	158.6	193.3
Other (income) expense	(2.1)	3.7	(6.3)	5.9
Income before income taxes	93.2	4.2	99.8	10.8
Tax expense (benefit)	3.4	(0.7)	2.7	(25.2)
Equity in earnings of subsidiaries	0	0	0	0
Net income	89.8	4.9	97.1	36.0
Other comprehensive income (loss)	(136.1)	37.1	(180.3)	55.3
Comprehensive income (loss)	$ (46.3)	$ 42.0	$ (83.2)	$ 91.3

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