Other Assets - Summary of Finance Lease Receivables (Detail) - INR (₨) ₨ in Millions	Mar. 31, 2018	Mar. 31, 2017
Disclosure of recognised finance lease as assets by lessee [line items]
Gross investment in lease	₨ 5,304	₨ 4,847
Less: Unearned finance income	(294)	(319)
Present value of minimum lease payment receivables	5,010	4,528
Present value of minimum lease payment receivables	5,010	4,528
Present value of minimum lease payment receivables	5,010	4,528
Non-current finance lease receivables	2,739	2,674
Current finance lease receivables	2,271	1,854
Not later than one year [member]
Disclosure of recognised finance lease as assets by lessee [line items]
Gross investment in lease	2,414	2,060
Present value of minimum lease payment receivables	2,271	1,854
Present value of minimum lease payment receivables	2,271	1,854
Present value of minimum lease payment receivables	2,271	1,854
Later than one year but not later than five years [member]
Disclosure of recognised finance lease as assets by lessee [line items]
Gross investment in lease	2,890	2,725
Present value of minimum lease payment receivables	2,739	2,616
Present value of minimum lease payment receivables	2,739	2,616
Present value of minimum lease payment receivables	₨ 2,739	2,616
Residual value risk [member]
Disclosure of recognised finance lease as assets by lessee [line items]
Gross investment in lease		62
Present value of minimum lease payment receivables		58
Present value of minimum lease payment receivables		58
Present value of minimum lease payment receivables		₨ 58

The amount of current finance lease receivables. [Refer: Finance lease receivables]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2017-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard
-URIDate 2017-03-09

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The aggregate of: (a) the minimum lease payments receivable by the lessor under a finance lease; and (b) any unguaranteed residual value accruing to the lessor. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2017-03-02&anchor=para_47_a&doctype=Standard&book=B
-URIDate 2017-03-09

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- Definition

The present value of minimum finance lease payments receivable. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

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- Definition

The amount of non-current finance lease receivables. [Refer: Finance lease receivables]

+ References

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- Definition

The difference for a finance lease between: (a) the gross investment in the lease, and (b) the net investment in the lease. The gross investment in the lease is the aggregate of: (a) the minimum lease payments receivable by the lessor under a finance lease; and (b) any unguaranteed residual value accruing to the lessor. The net investment in the lease is the gross investment in the lease discounted at the interest rate implicit in the lease. [Refer: Finance income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2017-03-02&anchor=para_47_b&doctype=Standard&book=B
-URIDate 2017-03-09

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