Accounts Receivable (Details) (USD $)	Dec. 31, 2012	Mar. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	$ 80,075,000	$ 65,089,000
Less allowances for discounts, returns and uncollectible accounts	(6,323,000)	(4,861,000)
Accounts receivable, net	73,752,000	60,228,000
Trade Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	78,689,000	55,721,000
Other Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	$ 1,386,000	$ 9,368,000