Earnings per share and stock plans (Details) (1) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Numerator For Basic And Diluted Earnings Per Share [Abstract]
Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest	$ 9,579	$ 8,515	$ 26,267	$ 17,561
Income from discontinued operations		0	0	409
Net income (loss)	$ 9,579	$ 8,515	$ 26,267	$ 17,970
Denominator For Basic And Diluted Earnings Per Share [Abstract]
Weighted Average Number Of Shares Outstanding Basic	19,451	19,313	19,406	19,256
Weighted Average Number Of Diluted Shares Outstanding	19,697	19,488	19,620	19,526

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

+ References+ Details

This element represents the overall income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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+ Details

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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-Glossary Weighted-Average Number of Common Shares Outstanding

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+ Details