Goodwill and Intangible Assets (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Indefinite-lived Intangible Assets [Line Items]
Goodwill	$ 477,000,000		$ 477,000,000		$ 476,000,000
Goodwill impairment charges	0	$ 0	0	$ 0
Accumulated impairment loss	0		0		$ 0
Amortization expense	1,000,000	2,000,000	5,000,000	6,000,000
Net cash paid	3,000,000
Trade names [Member]
Indefinite-lived Intangible Assets [Line Items]
Intangible asset impairment charges	$ 0	$ 0	$ 0	$ 0

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 after accumulated impairment loss of 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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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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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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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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