Summary of Accounting Policies (Allowance for Doubtful Accounts) (Details) (USD $) In Thousands	12 Months Ended
	Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Summary of Accounting Policies
Balance at Beginning of Year	$ 13,163	$ 29,020	$ 16,732
Charged to Costs and Expenses	4,043	44,066	73,845
Deductions/ Write-offs	(3,818)	(59,923)	(61,557)
Balance at End of Year	$ 13,388	$ 13,163	$ 29,020