Earnings Per Share (Computation of basic and diluted earnings per share) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Numerator For Basic And Diluted Earnings Per Share [Abstract]
Net income (loss)	$ 8,252	$ 6,676	$ 16,688	$ 9,455
Denominators [Abstract]
Weighted Average Number Of Shares Outstanding Basic	19,419	19,274	19,384	19,224
Effect of dilutive employee stock options and other share-based awards	$ 162	$ 197	$ 162	$ 287
Weighted Average Number Of Diluted Shares Outstanding	19,581	19,471	19,546	19,511

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.

+ References+ Details

- 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.

+ References

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-Glossary Weighted-Average Number of Common Shares Outstanding

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