Valuation and Qualifying Accounts (Schedule of Valuation and Qualifying Accounts) (Details) (Accounts Receivable - Allowances for Doubtful Accounts [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Mar. 31, 2013
Accounts Receivable - Allowances for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 31,757		$ 28,650		$ 31,845
Additions charged to costs and expenses	15,843		20,310		23,427
Additions charged to other accounts	3,228	[1]	7,163	[1]	4,034	[1]
Deductions	(23,812)	[2]	(24,366)	[2]	(30,656)	[2]
Balance at end of period	$ 27,016		$ 31,757		$ 28,650

[1] Principally reflects subsequent collections of accounts previously written-off.

[2] Write-off of uncollectible accounts.