Related Parties (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Related Party [Abstract]
Short-term employee benefits	$ 101	$ 99
Post-employment benefits	8	7
Share-based payments	86	79
Termination benefits	1	2
Other long-term benefits	3	3
Total	$ 199	$ 190

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2025-01-01
-Paragraph 17
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2025-en-r&anchor=para_17&doctype=Standard
-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 227
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_227&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 227
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_227&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_KeyManagementPersonnelCompensation
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2025-en-r&anchor=para_17_c&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_KeyManagementPersonnelCompensationOtherLongtermBenefits
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2025-en-r&anchor=para_17_b&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_KeyManagementPersonnelCompensationPostemploymentBenefits
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2025-en-r&anchor=para_17_e&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_KeyManagementPersonnelCompensationSharebasedPayment
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2025-en-r&anchor=para_17_a&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2025-en-r&anchor=para_17_d&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_KeyManagementPersonnelCompensationTerminationBenefits
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Related Party [Abstract]

+ References

No definition available.

+ Details

Name:	mfc_RelatedPartyAbstract
Namespace Prefix:	mfc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration