v3.20.2

Fair value of financial instruments - Conversion Option Derivative (Details) - Derivative Financial Instruments, Assets - Level 3 - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance of liability	$ 3.2	$ 1.2
Total unrealized gain (loss)	(1.8)	1.5
Currency transaction loss	0.1	0.1
Ending balance of liability	$ 1.5	$ 2.8

X

- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use translating currencies.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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X

- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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