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Goodwill and Intangible Assets Goodwill Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Goodwill [Line Items]
Goodwill	$ 2,322,928	$ 2,433,784	$ 2,231,303
Goodwill, Transfers		0
Life Science Member [Member]
Goodwill [Line Items]
Goodwill, Transfers		0
Healthcare Specialty Services [Member]
Goodwill [Line Items]
Goodwill, Transfers		(1,855)
Healthcare Products [Member]
Goodwill [Line Items]
Goodwill, Transfers		0
Applied Sterilization Technologies [Member]
Goodwill [Line Items]
Goodwill, Transfers		1,855
goodwill acquired or allocated member [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	3,232	35,766
Foreign Currency Gain (Loss) [Member]
Goodwill [Line Items]
Goodwill	(114,088)	166,715
Healthcare Specialty Services [Member]
Goodwill [Line Items]
Goodwill	374,910	388,025	375,879
Healthcare Specialty Services [Member] \| goodwill acquired or allocated member [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	(907)	3,501
Healthcare Specialty Services [Member] \| Foreign Currency Gain (Loss) [Member]
Goodwill [Line Items]
Goodwill	(12,208)	10,500
Life Science Member [Member]
Goodwill [Line Items]
Goodwill	147,795	148,816	146,514
Life Science Member [Member] \| goodwill acquired or allocated member [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	0	0
Life Science Member [Member] \| Foreign Currency Gain (Loss) [Member]
Goodwill [Line Items]
Goodwill	(1,021)	2,302
Healthcare Products [Member]
Goodwill [Line Items]
Goodwill	397,284	404,674	377,765
Healthcare Products [Member] \| goodwill acquired or allocated member [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	(1,202)	16,418
Healthcare Products [Member] \| Foreign Currency Gain (Loss) [Member]
Goodwill [Line Items]
Goodwill	(6,188)	10,491
Applied Sterilization Technologies [Member]
Goodwill [Line Items]
Goodwill	1,402,939	1,492,269	$ 1,331,145
Applied Sterilization Technologies [Member] \| goodwill acquired or allocated member [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	5,341	15,847
Applied Sterilization Technologies [Member] \| Foreign Currency Gain (Loss) [Member]
Goodwill [Line Items]
Goodwill	$ (94,671)	$ 143,422