v3.19.1

Leases (Supplemental Balance Sheet Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Jan. 01, 2019
Operating Leases [Abstract]
Operating lease, right-of-use asset	$ 12.3	$ 10.8
Current operating lease liabilities	4.3
Long-term operating lease liabilities	8.8
Total operating lease liabilities	13.1	$ 11.5
Finance Leases [Abstract]
Finance lease right-of-use asset, gross	17.4
Finance lease right-of-use asset, accumulated amortization	(8.2)
Finance lease right-of-use asset, net	9.2
Current finance lease liabilities	3.8
Long-term finance lease liabilities	5.5
Total finance lease liabilities	$ 9.3
Weighted average remaining lease term
Operating leases	3 years 7 months 29 days
Finance leases	3 years 4 months 24 days
Weighted average discount rate
Operating leases	5.80%
Finance leases	2.40%

Finance Lease, Right-of-Use Asset, Accumulated Amortization

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- Definition

Finance Lease, Right-of-Use Asset, Gross

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- Definition

Finance Leases [Abstract]

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- Definition

Operating Leases [Abstract]

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No definition available.

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- Definition

Weighted Average Discount Rate [Abstract]

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- Definition

Weighted Average Remaining Lease Term [Abstract]

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No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Balance Type:	credit
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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

+ References

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- Definition

Amount of lessee's right to use underlying asset under finance lease.

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Data Type:	xbrli:monetaryItemType
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- Definition

Weighted average discount rate for finance lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(4)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

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- Definition

Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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