Acquisitions - Narrative (Details) (USD $)	12 Months Ended			0 Months Ended		12 Months Ended		25 Months Ended	0 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Jun. 13, 2011 Cornell Dubilier Foil, LLC	Feb. 21, 2012 Niotan Incorporated	Mar. 31, 2014 Niotan Incorporated	Mar. 31, 2013 Niotan Incorporated	Mar. 31, 2014 Niotan Incorporated	Feb. 21, 2012 Niotan Incorporated Developed technology	Feb. 21, 2012 Niotan Incorporated Software
Acquisitions
Purchase price				$ 15,000,000
Working capital adjustment				526,000	403,000
Purchase price paid at closing (net of cash received)	0	0	42,613,000	11,600,000	30,500,000
Purchase price installment paid on the first anniversary of the acquisition closing date				1,000,000
Purchase price installment payable on each of the next two anniversaries of the acquisition closing date				1,000,000
Goodwill	35,584,000	35,584,000	36,676,000	1,092,000	35,584,000
Intangible assets				1,660,000	22,420,000				22,300,000	120,000
Discounted purchase price				15,341,000	81,972,000
Additional deferred payments					45,000,000
Period of payment of additional deferred payments after the closing					30 months
Installment payment						20,000,000	15,000,000
Aggregate amount of quarterly royalty payments					10,000,000
Royalty payments during period								1,500,000
Deferred payments						$ 18,600,000		$ 18,600,000
Useful Life (years)									18 years	4 years
Period of completion of development of assets									4 years