Shareholders' Equity (Shareholders' Equity Activities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Shareholders Equity [Line Items]
Beginning Balance	$ 935	$ 2,439
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(40)
Stock-based compensation	5	5
Common stock issued upon exercise of stock options	1	4
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net		1
Dividends declared to shareholders	(12)us-gaap_DividendsCommonStockCash	(12)us-gaap_DividendsCommonStockCash
Repurchases of common stock	(16)	56
Issuance of ESPP shares	1	2
Distributions to noncontrolling interests	(7)	(19)
Net income (loss)	51us-gaap_ProfitLoss	(20)us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax	(46)	17
Ending Balance	872	2,361
Additional Paid-in Capital [Member]
Shareholders Equity [Line Items]
Beginning Balance	2,091	2,065
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(40)
Stock-based compensation	5	5
Common stock issued upon exercise of stock options	1	4
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net		1
Dividends declared to shareholders	0	0
Repurchases of common stock	0	0
Issuance of ESPP shares	(1)	0
Distributions to noncontrolling interests	0	0
Net income (loss)	0	0
Other comprehensive income (loss), net of tax	0	0
Ending Balance	2,056	2,075
Retained Earnings [Member]
Shareholders Equity [Line Items]
Beginning Balance	439	1,748
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	0
Stock-based compensation		0
Common stock issued upon exercise of stock options	0	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net		0
Dividends declared to shareholders	(12)	12
Repurchases of common stock	0	0
Issuance of ESPP shares	0	0
Distributions to noncontrolling interests	0	0
Net income (loss)	44	(43)
Other comprehensive income (loss), net of tax	0	0
Ending Balance	471	1,693
Treasury Stock [Member]
Shareholders Equity [Line Items]
Beginning Balance	(712)	(610)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	0
Stock-based compensation	0	0
Common stock issued upon exercise of stock options	0	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net		0
Dividends declared to shareholders	0	0
Repurchases of common stock	(16)	(56)
Issuance of ESPP shares	2	2
Distributions to noncontrolling interests	0	0
Net income (loss)	0	0
Other comprehensive income (loss), net of tax	0	0
Ending Balance	(726)	(664)
Accumulated Other Comprehensive Income (Loss) [Member]
Shareholders Equity [Line Items]
Beginning Balance	(876)	(740)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	0
Stock-based compensation	0	0
Common stock issued upon exercise of stock options	0	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net		0
Dividends declared to shareholders	0	0
Repurchases of common stock	0	0
Issuance of ESPP shares	0	0
Distributions to noncontrolling interests	0	0
Net income (loss)	0	0
Other comprehensive income (loss), net of tax	(46)	17
Ending Balance	(922)	(723)
Noncontrolling Interests [Member]
Shareholders Equity [Line Items]
Beginning Balance	(7)	(24)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	0
Stock-based compensation	0	0
Common stock issued upon exercise of stock options	0	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net		0
Dividends declared to shareholders	0	0
Repurchases of common stock	0	0
Issuance of ESPP shares	0	0
Distributions to noncontrolling interests	(7)	(19)
Net income (loss)	7	23
Other comprehensive income (loss), net of tax	0	0
Ending Balance	(7)	(20)
Scenario, Previously Reported [Member]
Shareholders Equity [Line Items]
Other comprehensive income (loss), net of tax	$ (46)	$ 17

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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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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