Acquisitions and Divestiture - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended							3 Months Ended		3 Months Ended		12 Months Ended			1 Months Ended				1 Months Ended		12 Months Ended		12 Months Ended
	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2012 Completed technology Minimum	Sep. 30, 2012 Completed technology Maximum	Sep. 30, 2012 Customer relationships Minimum	Sep. 30, 2012 Customer relationships Maximum	Dec. 31, 2011 CeligoCell Cytometer product line	Dec. 30, 2011 CeligoCell Cytometer product line	Dec. 31, 2011 CeligoCell Cytometer product line Completed technology	Dec. 31, 2011 CeligoCell Cytometer product line Trade Name	Sep. 30, 2011 Nexus	Sep. 30, 2010 Nexus	Jul. 25, 2011 Nexus	Jul. 25, 2011 Nexus Completed technology	Jul. 25, 2011 Nexus Trade Name	Jul. 25, 2011 Nexus Customer relationships Minimum	Jul. 25, 2011 Nexus Customer relationships Maximum	Jul. 25, 2011 Nexus Customer relationships System	Jul. 25, 2011 Nexus Customer relationships Consumables and service	Sep. 30, 2011 RTS Life Science Limited	Apr. 01, 2011 RTS Life Science Limited	Sep. 30, 2012 RTS Life Science Limited Completed technology Minimum	Sep. 30, 2012 RTS Life Science Limited Completed technology Maximum	Sep. 30, 2012 RTS Life Science Limited Customer relationships	Sep. 30, 2012 RTS Life Science Limited Trademarks and trade names
Business Acquisition [Line Items]
In-process research and development		$ 3,026,000
Business acquisition, cash payment										8,700,000
Business acquisition deferred cash payable										500,000
Cash flow discount rate											25.00%					17.00%		17.00%	18.00%
Amortizable lives					2 years	10 years	4 years	13 years			6 years	6 years				6 years	2 years			6 years	13 years			5 years	7 years	7 years	3 years
Transaction costs related to acquisition									105,000				719,000									188,000
Total purchase price, net of cash acquired										9,216,000					84,928,000								3,381,000
Royalty rate																6.00%
Revenues		519,451,000	688,105,000	592,972,000									4,900,000
Net income (loss)		136,789,000	130,385,000	59,841,000									(3,200,000)
Net losses, charges to expense the step-up of acquired inventories													700,000
Net losses, charges for excess and obsolete inventory													600,000
Gain from bargain purchase														12,000,000
Proceeds from the sale of the contract manufacturing business			78,249,000
Considerations received from asset sale			1,300,000
Additional estimated proceeds from sale of business	2,500,000
Transaction expenses			2,300,000
Sale of contract manufacturing business			45,009,000
Gain recognized on sale of assets, income tax			$ 2,400,000