Equity - Total Number of Shares Authorized and Issued (Detail) - shares	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Total number of authorized shares
Common shares, no par value	7,086,000,000	7,086,000,000	7,086,000,000
Total number of issued shares
Balance at beginning of year	5,280,000,000	5,280,000,000	1,811,428,430
Changes during the year	(747,000,000)		3,468,571,570
Balance at end of year	4,533,000,000	5,280,000,000	5,280,000,000

The number of shares authorised.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph B10
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_B10_a_i&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 160
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_160_a_i&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 79
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_79_a_i&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_NumberOfSharesAuthorised
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant