Reconciliation of Beginning and Ending Balance of Unrecognized Tax Benefits (Detail) ₨ in Millions, $ in Millions	12 Months Ended
Mar. 31, 2015 INR (₨)	Mar. 31, 2015 USD ($)	Mar. 31, 2014 INR (₨)
Income Tax Contingency [Line Items]
Opening balance	₨ 648.3	$ 10.4	₨ 648.3
Increase/(decrease) related to prior year tax positions	0.0	0.0	0.0
Closing balance	₨ 648.3	$ 10.4	₨ 648.3

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No definition available.

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- Definition

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

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

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

Reference 2: 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

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- Definition

The net amount of all increases and decreases in unrecognized tax benefits for the period.

+ References

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