Additional Consolidated Balance Sheets Information Level 4 (Details) (USD $) In Thousands	Jun. 30, 2011	Mar. 31, 2011
Employee-related Liabilities	$ 15,643	$ 16,160
Accrued Vacation	7,973	6,379
Accrued Bonuses	2,031	13,925
Accrued Liabilities for Commissions, Expense and Taxes	6,208	11,985
Other Postretirement Benefits Payable	3,274	3,274
Pension and Other Postretirement and Postemployment Benefit Plans, Liabilities	607	528
Employee-related Liabilities, Current	35,736	52,251
Deferred Revenue	37,627	34,396
Self Insurance Reserve, Current	2,800	3,610
Accrued Sales Commission	7,063	7,354
Product Warranty Accrual	8,594	7,509
Accrued Liabilities	76,660	73,831
Self Insurance Reserve, Noncurrent	10,233	10,233
Other Postretirement Benefits Payable, Noncurrent	19,620	20,526
Defined Benefit Pension Plan, Liabilities, Noncurrent	7,578	8,006
Pension and Other Postretirement and Postemployment Benefit Plans, Liabilities, Noncurrent	4,288	3,897
Accrued Income Taxes, Noncurrent	6,877	9,140
Other Liabilities	10,499	4,810
Other Accrued Liabilities	20,576	20,962
Other Liabilities, Noncurrent	$ 59,095	$ 56,612