The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Goodwill [Line Items]
Goodwill, additions from new business combinations			$ 42.4
Amortization expense, intangible assets	$ 4.9	$ 5.3	9.0	$ 10.5
Earn-Out Arrangements [Member]
Goodwill [Line Items]
Accruals of acquisition-related contingent consideration				5.8
Goodwill, Gross [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)			4.6	8.0
Goodwill, Accumulated Impairment Losses [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)			$ (2.6)	$ (4.2)