Pro Forma Results of Consolidated Statement of Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Business Acquisition, Pro Forma Information [Line Items]
Pro forma revenue	$ 94,221	$ 91,566	$ 263,009	$ 244,003
Pro forma net income	$ 11,038	$ 1,813	$ 20,036	$ 2,409
Pro forma income per share, Basic	$ 0.26	$ 0.04	$ 0.48	$ 0.06
Pro forma income per share, Diluted	$ 0.26	$ 0.04	$ 0.47	$ 0.06
Pro forma shares outstanding, Basic	41,709	41,523	41,715	42,126
Pro forma shares outstanding, Diluted	42,298	42,303	42,364	42,815

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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-Name Statement of Financial Accounting Standard (FAS)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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No definition available.

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