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LEASES - Summary of Lease Liabilities Measured at Present Value of Lease Payments to be Made Over Lease Term (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Feb. 28, 2026	Dec. 31, 2025
Analyzed into:
Current portion	$ 11.2		$ 7.4
Non-current portion	112.1		87.2
Janssen
Analyzed into:
Carrying amount at March 31, 2026		$ 30.6
Lease liabilities
Disclosure Of Detailed Information About Lease Liabilities [Line Items]
Carrying amount at January 1, 2026	94.6
Additions	30.7
Accretion of interest recognized during the period	0.9
Payments	(2.3)
Exchange realignment	(0.6)
Carrying amount at March 31, 2026	123.3
Analyzed into:
Current portion	11.2
Non-current portion	112.1
Carrying amount at March 31, 2026	$ 123.3		$ 94.6

X

- Definition

The cash outflow for leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 53
-Subparagraph g
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-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 115
-Subparagraph f
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-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 115
-Subparagraph f
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_115_f&doctype=Standard
-URIDate 2025-03-27

+ Details

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Balance Type:	credit
Period Type:	duration

X

- Definition

The amount of current lease liabilities. [Refer: Lease liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 47
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2025-03-27

+ Details

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X

- Definition

The increase (decrease) in liabilities arising from financing activities resulting from the effect of changes in foreign exchange rates. [Refer: Liabilities arising from financing activities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 44B
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_44B_c&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 166
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166_c&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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-IssueDate 2025-01-01
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-URIDate 2025-03-27

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X

- Definition

The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 47
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2025-03-27

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X

- References

No definition available.

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X

- Definition

The amount of non-current lease liabilities. [Refer: Lease liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
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-URIDate 2025-03-27

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X

- Definition

Disclosure of detailed information about lease liabilities.

+ References

No definition available.

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- Definition

Increase in lease liabilities.

+ References

No definition available.

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- Definition

Increase of lease liabilities balance.

+ References

No definition available.

+ Details

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