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 accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill and Intangible Assets Goodwill (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Goodwill [Line Items]
Goodwill, Acquired During Period			$ 0
Goodwill, Impaired, Accumulated Impairment Loss	$ 0		0
Amortization of intangible assets	$ 15,800,000	$ 18,000,000.0	$ 51,700,000	$ 54,000,000.0
Weighted Average
Goodwill [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period			4 years