Summary of Significant Accounting Policies (Life Settlement Contracts) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Life Settlement Contracts, Fair Value Method, Number of Contracts, Fiscal Year Maturity [Abstract]
Life settlement contracts, fair value method, number of contracts, maturing in next twelve months	70
Life settlement contracts, fair value method, number of contracts, maturing in year two	60
Life settlement contracts, fair value method, number of contracts, maturing in year three	60
Life settlement contracts, fair value method, number of contracts, maturing in year four	50
Life settlement contracts, fair value method, number of contracts, maturing in year five	40
Life settlement contracts, fair value method, number of contracts, maturing after year five	390
Life settlement contracts, fair value method, number of contracts	670
Life settlement contracts, fair value, maturing in next twelve months	$ 15
Life settlement contracts, fair value, maturing in year two	13
Life settlement contracts, fair value, maturing in year three	11
Life settlement contracts, fair value, maturing in year four	9
Life settlement contracts, fair value, maturing in year five	7
Life settlement contracts, fair value, maturing after year five	45
Life settlement contracts, fair value	100	117
Life settlement contracts, fair value method, face value, maturing in next twelve months	41
Life settlement contracts, fair value method, face value, maturing in year two	36
Life settlement contracts, fair value method, face value, maturing in year three	34
Life settlement contracts, fair value method, face value, maturing in year four	30
Life settlement contracts, fair value method, face value, maturing in year five	27
Life settlement contracts, fair value method, face value, maturing after year five	237
Life settlement contracts, fair value method, face value	$ 405

Fair value amount of life settlement contracts accounted for under the fair value method maturing after the fifth fiscal year following the latest fiscal year.

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Fair value amount of life settlement contracts accounted for under the fair value method maturing in the next fiscal year following the latest fiscal year.

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Fair value amount of life settlement contracts accounted for under the fair value method maturing in the fifth fiscal year following the latest fiscal year.

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Fair value amount of life settlement contracts accounted for under the fair value method maturing in the fourth fiscal year following the latest fiscal year.

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Fair value amount of life settlement contracts accounted for under the fair value method maturing in the third fiscal year following the latest fiscal year.

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Fair value amount of life settlement contracts accounted for under the fair value method maturing in the second fiscal year following the latest fiscal year.

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Fair value amount of life settlement contracts accounted for under the fair value method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Life Settlement Contract

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 30

-Section 50

-Paragraph 8

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method.

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-Name Accounting Standards Codification

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method maturing after the fifth fiscal year following the latest fiscal year.

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method maturing in the next fiscal year following the latest fiscal year.

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method maturing in the fifth fiscal year following the latest fiscal year.

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method maturing in the third fiscal year following the latest fiscal year.

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method maturing in the second fiscal year following the latest fiscal year.

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Number of life settlement contracts accounted for under the fair value method.

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-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6516907

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-Name Accounting Standards Codification

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