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.

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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Goodwill [Line Items]
Goodwill, additions from new business combinations			$ 9.8
Goodwill, measurement period adjustments			3.8
Amortization expense, intangible assets	$ 5.2	$ 6.0	15.4	$ 15.0
Goodwill, Gross [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)			(3.5)
Goodwill, Accumulated Impairment Loss [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)			$ 2.0