Warranty (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Aug. 31, 2012	Aug. 31, 2011	May 31, 2012
Summary of accrued warranty and related expenses
Balance at the beginning of the period	$ 5,870	$ 4,966
Accruals for warranties	1,685	1,355
Settlements made during the period	(1,357)	(1,330)
Balance at the end of the period	6,198	4,991
Non-current balance included in other deferred liabilities	2,000	1,600
Accrued warranty and related expenses	$ 4,198	$ 3,391	$ 3,870

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

+ References+ Details