Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Goodwill [Line Items]
Goodwill, additions from new business combinations	$ 39.9
Amortization expense, intangible assets	4.8	$ 4.9
Goodwill, Gross [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)	2.0
Goodwill, Accumulated Impairment Loss [Member]
Goodwill [Line Items]
Goodwill, currency translation gains (losses)	$ (1.7)

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 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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