Basis of Presentation, Business Description and Summary of Significant Accounting Policies (Details Textual) (USD $) Share data in Millions, unless otherwise specified	0 Months Ended				1 Months Ended				12 Months Ended				12 Months Ended	0 Months Ended		0 Months Ended	12 Months Ended		12 Months Ended
	Mar. 31, 2014 Observation	Sep. 24, 2012 Observation	Feb. 13, 2012 Observation	Feb. 10, 2012 Observation	Apr. 21, 2014	Feb. 25, 2014	Oct. 15, 2012	Mar. 05, 2012	May 31, 2014 Intangible_Asset Investment	May 31, 2013 Investment	May 31, 2012	Jun. 30, 2012	May 31, 2014 Clinical Devices, B.V. [Member] Trademark-NAMIC [Member]	May 22, 2012 Navilyst [Member]	May 31, 2014 Navilyst [Member]	May 22, 2012 Navilyst [Member] Trademark-NAMIC [Member]	May 31, 2014 Navilyst [Member] Trademark-NAMIC [Member]	May 31, 2014 RITA [Member]	May 31, 2014 Maximum [Member]	May 31, 2014 Minimum [Member]
Business Acquisition [Line Items]
Costs for quality call to action program									$ 3,200,000
Number of observations	3	5	6	12
Number of business days to provide response to FDA					15 days	15 days	15 days	15 days
Short Term Investments Maturity Period									less than three months
Investments in auction rate securities that failed auctions									1,809,000	1,800,000
Number of investments									2	2
Accounts receivables period due																			90 days	30 days
Weighted average useful life														10 years					20 years	3 years
Acquired intangible asset													3,600,000			28,600,000	28,600,000
Number of Indefinite Lived Intangible Assets									1
Restocking charge percentage									20.00%
Undamaged product expiration date																				12 months
Federal net operating losses, unutilized															17,500,000			15,800,000
Federal net operating losses, utilized																		7,100,000
Estimated net operating losses, prior to utilization									13,000,000						13,000,000			13,600,000
Potential amount of undiscounted future contingent consideration									78,100,000
Milestones associated with the contingent consideration									51,100,000
Reflected in current portion of contingent consideration									16,300,000
Interest expense on derivative financial instruments										61,000
Notional amount of interest rate swap agreement									100,000,000
Fixed interest rate payments												3.26%
Stock-based compensation, options vested, percentage									88.00%
Stock-based compensation, options forfeiture rate									12.00%
Dividend paid									$ 0
Antidilutive securities excluded from computation of diluted earnings per share									2.3	2.9	2.3