Leases - Schedule of cash flow information related to leases (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$ 90.5
Operating cash flows from finance leases	0.4
Financing cash flows from finance leases	1.0
Leased assets obtained in exchange for new operating liabilities	29.2
Leased assets obtained in exchange for new finance lease liabilities	$ 3.6

Cash Paid In Amounts Included In Measurement Of Lease Liabilities [Abstract]

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- Definition

Amount of interest paid on finance lease liability.

+ References

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-Publisher FASB
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-Topic 842
-SubTopic 20
-Section 50
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+ Details

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- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977

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-Publisher FASB
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-Section 50
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-Subparagraph (g)(1)
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 45
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977

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- Definition

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

+ References

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-Publisher FASB
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- Definition

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

+ References

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