Lease Obligations (Finance Leases) (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Finance leases, assets, gross	$ 353.0	$ 337.6
Finance leases, assets, net	271.3	$ 246.8
Finance leases, assets, depreciation	$ 10.0

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 1
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Balance Type:	debit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under 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 1
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Balance Type:	debit
Period Type:	instant

- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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-Publisher FASB
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- References

No definition available.

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