Initial public offering, authorized amount.

No definition available.

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- Definition

Maximum period for listing of so called upper layer designation.

+ References

No definition available.

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- Definition

Sale of stock consideration received on transaction assigned to subsidiary.

+ References

No definition available.

+ Details

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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Subsequent Events - Additional Information (Detail) - INR (₨) ₨ / shares in Units, ₨ in Millions, shares in Millions	Jul. 02, 2025	Apr. 19, 2025	Oct. 19, 2024	Mar. 31, 2025	Mar. 31, 2024
Subsequent Event [Line Items]
Common stock par or stated value per share				₨ 1	₨ 1
HDB Financial Services Limited [Member]
Subsequent Event [Line Items]
Maximum period for listing of so called upper layer designation			3 years
IPO [Member] \| HDB Financial Services Limited [Member]
Subsequent Event [Line Items]
Common stock par or stated value per share			₨ 10
Initial public offering, authorized amount			₨ 100,000.0
Subsequent Event [Member] \| IPO [Member] \| HDB Financial Services Limited [Member]
Subsequent Event [Line Items]
Sale of stock, consideration received on transaction	₨ 100,000.0
Sale of stock number of shares issued in transaction	135.1
Sale of stock price per share	₨ 740
Sale of stock consideration received on transaction assigned to subsidiary	₨ 25,000.0
Sale of stock percentage of ownership after transaction	74.70%
O 2025 A Dividends [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend paid, per share amount		₨ 22
Dividend paid, total amount		₨ 168,348.9