Insurance (Liabilities for Unpaid Claims and Claim Expense) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Liabilities for Unpaid Claims and Claim Expenses
Balance at January 1,	$ 10,630	$ 10,436	$ 10,117
Less: Reinsurance recoverables	1,661us-gaap_ReinsuranceRecoverables	1,581us-gaap_ReinsuranceRecoverables	1,436us-gaap_ReinsuranceRecoverables
Net balance at January 1,	8,969	8,855	8,681
Incurred related to:
Current year	9,358	8,660	8,399
Prior years	(70)	(86)	(69)
Total incurred	9,288	8,574	8,330
Paid related to:
Current year	(6,714)	(6,083)	(5,689)
Prior years	(2,383)	(2,377)	(2,467)
Total paid	(9,097)	(8,460)	(8,156)
Net balance at December 31,	9,160	8,969	8,855
Add: Reinsurance recoverables	1,876us-gaap_ReinsuranceRecoverables	1,661us-gaap_ReinsuranceRecoverables	1,581us-gaap_ReinsuranceRecoverables
Balance at December 31,	$ 11,036	$ 10,630	$ 10,436

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

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Amount of payments to settle claims incurred in the current period and related claims settlement costs.

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Amount of payments to settle claims incurred in prior periods and related claims settlement costs.

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Amount of expense for claims incurred and costs incurred in the claim settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of payments to settle insured claims and pay costs incurred in the claims settlement process.

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Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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Amount of expense for claims incurred in the current reporting period and related claims settlement costs.

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Amount of expense for claims incurred in prior reporting periods and related claims settlement costs.

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