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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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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Goodwill [Line Items]
Goodwill, additions from new business combinations			$ 9.8
Goodwill, measurement period adjustments			1.6
Amortization expense, intangible assets	$ 5.4	$ 4.9	10.3	$ 9.0
Goodwill, Gross [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)			(5.8)
Goodwill, Accumulated Impairment Loss [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)			$ 3.2