Certain Financial Statement Information - Schedule of Other assets (Details) (USD $)	12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Schedule of other assets
Non-current portion of prepaid expenses	$ 7,866,000		$ 4,193,000
Strategic investments	3,000,000	[1]	4,750,000	[1]
Other	0		1,331,000
Total other assets	10,866,000		10,274,000
Impariment charge of non-marketable strategic investments	$ 2,300,000		$ 1,000,000

[1] During the fiscal year ended March 31, 2013 and 2012, the Company recognized an impairment charge of its non-marketable strategic investment of $2.3 million and $1.0 million. Refer to Note 2 to the Consolidated Financial Statements for further details.