Capital Structure [Line Items]

No definition available.

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- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of the reduction or elimination during the period of a noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Value of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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Balance Type:	na
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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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-Publisher FASB
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- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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- Definition

This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.

+ References

No definition available.

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Capital Structure - Schedule of Changes in Stockholders' Deficit and Equity (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Capital Structure [Line Items]
Beginning Balances			$ (4,995)
Comprehensive income	$ 902	$ 822	2,265	$ 1,617
Repurchase of common stock			(893)
Dividends and distributions			(435)
Share-based benefit plans			(18)
Dispositions of entities with noncontrolling interests			(53)
Other			4
Ending Balances	(4,125)		(4,125)
Common Stock [Member]
Capital Structure [Line Items]
Beginning Balances			4
Repurchase of common stock			(1)
Ending Balances	$ 3		$ 3
Beginning Balances, Shares			350,092,000
Repurchase of common stock, shares			(9,040,000)
Share-based benefit plans, Shares			5,708,000
Ending Balances, Shares	346,760,000		346,760,000
Accumulated Other Comprehensive Loss [Member]
Capital Structure [Line Items]
Beginning Balances			$ (278)
Comprehensive income			17
Ending Balances	$ (261)		(261)
Retained Deficit [Member]
Capital Structure [Line Items]
Beginning Balances			(6,532)
Comprehensive income			1,964
Repurchase of common stock			(892)
Dividends and distributions			(250)
Share-based benefit plans			(18)
Other			(3)
Ending Balances	(5,731)		(5,731)
Equity Attributable to Noncontrolling Interests [Member]
Capital Structure [Line Items]
Beginning Balances			1,811
Comprehensive income			284
Dividends and distributions			(185)
Dispositions of entities with noncontrolling interests			(53)
Other			7
Ending Balances	$ 1,864		$ 1,864