Represents the estimated fair value of the long-term debt instrument as a percentage of carrying value.

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

Fair value portion of assets classified as held for sale.

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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

Fair value portion of investments accounted under the equity method.

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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

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Millions	9 Months Ended
FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair value of assets and liabilities measured on recurring basis
Impairment charges	$ 29	$ 326
Charges to write-down assets held for sale to their estimated fair value		$ 3
Other impairment charges	3
Chicago Facilities \| Discontinued Operations, Held-for-sale
Fair value of assets and liabilities measured on recurring basis
Charges to write-down assets held for sale to their estimated fair value	17
Aspen Facilities \| Discontinued Operations, Held-for-sale
Fair value of assets and liabilities measured on recurring basis
Charges to write-down assets held for sale to their estimated fair value	9
Nonrecurring
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	45		$ 456
Other than temporarily impaired equity method investments			113
Non-financial assets	45		569
Nonrecurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	0		0
Other than temporarily impaired equity method investments			0
Non-financial assets	0		0
Nonrecurring \| Significant Other Observable Inputs (Level 2)
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	45		456
Other than temporarily impaired equity method investments			113
Non-financial assets	45		569
Nonrecurring \| Significant Unobservable Inputs (Level 3)
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	0		0
Other than temporarily impaired equity method investments			0
Non-financial assets	$ 0		$ 0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair value of assets and liabilities measured on recurring basis
Estimated fair value of the long-term debt instrument as a percentage of carrying value	100.90%		100.20%