Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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- Definition

As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of common shares (regardless of class), limited partnership units (regardless of class), non-preferential membership interests, or any other form of common equity regardless of investee entity legal form.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
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-Publisher FASB
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Redemption value, as if currently redeemable, of redeemable noncontrolling interest for other shares, units or ownership interests classified as temporary equity and the election has been made to accrete changes in redemption value to the earliest redemption date.

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

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

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Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

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- Definition

Amount to be paid per share that is classified as temporary equity by entity upon redemption. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

+ References

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-Topic 480
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REDEEMABLE NONCONTROLLING INTERESTS (Narrative) (Details) ₨ / shares in Units, ₨ in Millions, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2019 INR (₨)	Mar. 31, 2020	Dec. 31, 2019 INR (₨)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 INR (₨) ₨ / shares	Sep. 30, 2019	Apr. 21, 2016
Redeemable Noncontrolling Interest [Line Items]
Temporary equity redemption price per share (in INR per share) \| ₨ / shares					₨ 216
Consideration paid for redemption	₨ 24,800.0			$ 347.6
Payments to acquire interest in joint venture \| ₨			₨ 523.0
Tata Teleservices
Redeemable Noncontrolling Interest [Line Items]
Percentage of ownership	100.00%		50.00%
Consideration paid for redemption				$ 425.7	₨ 29,400.0
IDFC
Redeemable Noncontrolling Interest [Line Items]
Percentage of ownership			100.00%
India Transaction
Redeemable Noncontrolling Interest [Line Items]
Percentage of voting interest acquired							51.00%
Noncontrolling owners, ownership percentage				21.00%	21.00%	37.00%
Scenario, Forecast \| Tata Teleservices
Redeemable Noncontrolling Interest [Line Items]
Ownership percentage after transaction		92.00%
ATC, TIPL
Redeemable Noncontrolling Interest [Line Items]
Controlling interest percentage				79.00%	79.00%	63.00%
Noncontrolling owners, ownership percentage				21.00%	21.00%
Eure-et-Loir
Redeemable Noncontrolling Interest [Line Items]
Controlling interest percentage				51.00%	51.00%
Noncontrolling owners, ownership percentage				49.00%	49.00%
Carrying value \| $				$ 2.7