ACQUISITIONS Pro Forma Results of Consolidated Statement of Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Business Combinations [Abstract]
Pro forma revenue	$ 361,086	$ 338,720
Pro forma net income	$ 34,589	$ 10,594
Pro forma income per share:
Basic (in dollars per share)	$ 0.83	$ 0.25
Diluted (in dollars per share)	$ 0.82	$ 0.25
Pro forma shares outstanding
Basic (in shares)	41,665	42,035
Diluted (in shares)	42,322	42,750

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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

+ References

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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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The weighted average number of shares or units and dilutive common stock or unit equivalents outstanding in the calculation of proforma diluted earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

+ References

No definition available.

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The weighted average number of shares (units) outstanding in the calculation of pro forma basic earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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