Shareholders' Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Shareholders' equity activity [Roll Forward]
Balance at beginning of period	$ 16,298	$ 13,615
Shares repurchased		(500)
Stock plans	129	146
Payments of dividends to shareholders	(153)us-gaap_DividendsCommonStock	(127)us-gaap_DividendsCommonStock
Other	(7)us-gaap_StockholdersEquityOther	(2)us-gaap_StockholdersEquityOther
Comprehensive income (loss)	(644)	620
Balance at end of period	15,623	13,752
Company shareholders' equity
Shareholders' equity activity [Roll Forward]
Balance at beginning of period	16,267	13,581
Shares repurchased		(500)
Stock plans	129	146
Payments of dividends to shareholders	(153)	(127)
Other	(6)	(1)
Comprehensive income (loss)	(646)	626
Balance at end of period	15,591	13,725
Noncontrolling interest in consolidated subsidiaries
Shareholders' equity activity [Roll Forward]
Balance at beginning of period	31	34
Shares repurchased		0
Stock plans	0	0
Payments of dividends to shareholders	0	0
Other	(1)	(1)
Comprehensive income (loss)	2	(6)
Balance at end of period	$ 32	$ 27

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.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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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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Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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