Represents the number of entities disposed of by the reporting entity.

No definition available.

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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- Definition

Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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Acquisitions and Dispositions of Businesses - Dispositions (Details)	3 Months Ended			9 Months Ended
	Sep. 30, 2018 USD ($) disposal	Jun. 30, 2018 USD ($)	Sep. 30, 2017 USD ($) disposal	Sep. 30, 2018 USD ($) disposal	Sep. 30, 2017 USD ($) disposal
Dispositions
Gain (loss) on disposal of business	$ (3,000,000)		$ 0	$ (4,000,000)	$ (2,000,000)
Disposal Group, Not Discontinued Operations
Dispositions
Number of dispositions \| disposal	2		0	3	4
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Dispositions
Disposal group assets		$ 47,000,000
Disposal group liabilities		41,000,000
Amortization And Impairment Of Intangible Assets \| Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Dispositions
Impairment loss		$ 176,000,000		$ 175,000,000