Goodwill and Intangible Assets, Identifiable Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Identifiable intangible assets
Net book value		$ 26.4	$ 30.5
Impairment of Intangible Assets	$ 2.6
Customer relationships
Identifiable intangible assets
Original cost		38.5	38.5
Accumulated amortization		(9.5)	(8.0)
Net book value		$ 26.4	$ 30.5

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- References

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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