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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 842
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
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Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's 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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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Period Type:	instant

- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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-Publisher FASB
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Balance Type:	debit
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- Details

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Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Leases and Contingencies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Lessee, Lease, Description [Line Items]
Finance leases	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Clauses relating to automatic renewal			true
Operating lease expense	$ 0.9	$ 0.7	$ 1.7	$ 1.4
Minimum [Member] \| Operating Lease Arrangement for Real Estate [Member]
Lessee, Lease, Description [Line Items]
Lease term	36 months		36 months
Minimum [Member] \| Operating Lease Arrangement for Equipment [Member]
Lessee, Lease, Description [Line Items]
Lease term	60 months		60 months
Maximum [Member] \| Operating Lease Arrangement for Real Estate [Member]
Lessee, Lease, Description [Line Items]
Lease term	122 months		122 months
Maximum [Member] \| Operating Lease Arrangement for Equipment [Member]
Lessee, Lease, Description [Line Items]
Lease term	203 months		203 months