Cash Flow Information - Non-cash Activities (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Increase (decrease) in accrual for capital expenditures	$ 1.0	$ (3.6)
Operating leases, initial recognition	3.4	18.2
Operating leases, modifications and remeasurements	10.0	(9.5)
Finance leases, initial recognition	13.8	14.0
Finance leases, modifications and remeasurements	$ 31.8	$ 8.2

Increase (Decrease) in Capital Expenditures Accrued

No definition available.

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- Definition

Right-of-Use Asset Obtained in Exchange for Finance Lease Liability, Modifications and Remeasurements

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Right-of-Use Asset Obtained in Exchange for Operating Lease Liability, Modifications and Remeasurements

+ References

No definition available.

+ Details

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- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(2)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

+ Details

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

+ Details

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- References

No definition available.

+ Details

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