Reconciliation of Consolidated Liability for Gross Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Income Tax Disclosure [Abstract]
Balance at Beginning of Year	$ 24,802us-gaap_UnrecognizedTaxBenefits	$ 24,589us-gaap_UnrecognizedTaxBenefits	$ 25,890us-gaap_UnrecognizedTaxBenefits
Increase related to prior tax positions		213	215
Decrease related to prior tax positions	(24,802)		(1,516)
Balance at End of Year		$ 24,802us-gaap_UnrecognizedTaxBenefits	$ 24,589us-gaap_UnrecognizedTaxBenefits

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

+ Details

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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

+ Details

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