Goodwill and Intangible Assets Goodwill and Intangible Assets (Phantom) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Amortizing Intangibles:
Finite-Lived Intangible Assets, Amortization Expense, Year Two	$ 2.2
Finite-Lived Intangible Assets, Amortization Expense, Year Three	2.2
Finite-Lived Intangible Assets, Amortization Expense, Year Four	2.2
Finite-Lived Intangible Assets, Amortization Expense, Year Five	2.2
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 2.2
Useful life		16 years
Purchased technology, customer relationships and patents | Minimum [Member]
Amortizing Intangibles:
Useful life	3 years	3 years
Purchased technology, customer relationships and patents | Maximum
Amortizing Intangibles:
Useful life	18 years	18 years