Earnings Per Share (Computation of basic and diluted earnings per share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator for basic and diluted earnings per share:
Net income	$ 7,122	$ 8,252	$ 14,142	$ 16,688
Denominators:
Average basic shares outstanding	19,655	19,419	19,587	19,384
Effect of dilutive employee stock options and other share-based awards	$ 304	$ 162	$ 279	$ 162
Average diluted shares outstanding	19,959	19,581	19,866	19,546

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

-URI http://asc.fasb.org/extlink&oid=6528421

+ Details