Discontinued Operations (Income Statement Data) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations, net of tax	$ 0	$ 0	$ 0
Disposals of discontinued operations	42	(4)	(2)
Income tax (credit) expense	16	(10)	1
Disposals of discontinued operations, net of tax	26	6	(3)
Discontinued operations, net of tax	26	6	(3)
Discontinued operations, net of tax per share
- Basic (in dollars per share)	$ 0.05	$ 0.01	$ 0.00
- Diluted (in dollars per share)	$ 0.04	$ 0.01	$ 0.00
Putnam [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) Related to Settlement of Indemnity Agreement, Net of Tax	$ 28

Discontinued Operation, Gain (Loss) Related to Settlement of Indemnity Agreement, Net of Tax

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Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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Amount of tax expense or benefit on gain (loss), not previously recognized, resulting from the sale of a business component.

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Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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