Employee benefits - Employee benefit liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2016
Employee benefits
Salary and benefits payable	$ 112.7	$ 80.7
Share-based payment plans	13.7	5.3
Pension and other post-retirement benefits	215.1	241.5
Employee benefits	341.5	327.5
Current portion	(123.9)	(89.4)	$ (76.9)
Non current portion	$ 217.6	$ 238.1	$ 231.3

The amount of current provisions for employee benefits. [Refer: Provisions for employee benefits]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-URIDate 2017-03-09

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- Definition

The amount of liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services. [Refer: Share-based payment arrangements [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2017-01-01
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- Definition

The amount of non-current provisions for employee benefits. [Refer: Provisions for employee benefits]

+ References

+ Details

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- Definition

The amount of provisions for employee benefits. [Refer: Employee benefits expense; Provisions]

+ References

+ Details

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- Definition

The amount of deficit in a defined benefit plan. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Number 1
-IssueDate 2017-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard
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- References

No definition available.

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- Definition

The amount of salaries and benefits payable.

+ References

No definition available.

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