Goodwill and Intangible Assets - Narrative (Details) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Amortizing Intangibles:
Amortization charges	$ 2,100,000	$ 2,300,000	$ 2,000,000
Estimated amortization of intangible assets
2014	2,100,000
2015	2,100,000
2016	2,100,000
2017	2,100,000
2018	2,100,000
Thereafter	2,100,000
Total amortization	19,400,000
Goodwill and intangible assets
Goodwill impairment	$ 0	$ 1,092,000	$ 0
Purchased technology, customer relationships and patents | Weighted-average
Amortizing Intangibles:
Useful life	16 years	16 years