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A valuation allowance for financing receivables that are expected to be uncollectible.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Amount of direct write-downs of financing receivables charged against the allowance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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No definition available.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 14A
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No definition available.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Amount of loan with fixed rate of interest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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Investments- Carrying Value of Non-impaired Fixed Rate and Variable Rate Mortgage Loans (Details 13) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Net carrying value of impaired mortgage loans
Impaired mortgage loans with a valuation allowance					$ 5	$ 5
Impaired mortgage loans without a valuation allowance					0	0
Total impaired mortgage loans					5	5
Valuation allowance on impaired mortgage loans	$ 3	$ 3	$ 3	$ 3	3	3
Rollforward of the valuation allowance on impaired mortgage loans
Beginning balance	3	3	3	3
Charge offs	0	0	0	0
Ending balance	$ 3	$ 3	3	3
Non-impaired mortgage loans
Carrying value of non-impaired fixed rate and variable rate mortgage loans by debt service coverage ratio distribution
Fixed rate mortgage loans					3,788	3,933
Non-impaired mortgage loans \| Below 1.0
Carrying value of non-impaired fixed rate and variable rate mortgage loans by debt service coverage ratio distribution
Fixed rate mortgage loans					18	52
Non-impaired mortgage loans \| 1.0 - 1.25
Carrying value of non-impaired fixed rate and variable rate mortgage loans by debt service coverage ratio distribution
Fixed rate mortgage loans					318	321
Non-impaired mortgage loans \| 1.26 - 1.50
Carrying value of non-impaired fixed rate and variable rate mortgage loans by debt service coverage ratio distribution
Fixed rate mortgage loans					1,167	1,196
Non-impaired mortgage loans \| Above 1.50
Carrying value of non-impaired fixed rate and variable rate mortgage loans by debt service coverage ratio distribution
Fixed rate mortgage loans					$ 2,285	$ 2,364
Mortgage loans
Average carrying value and interest income recognized on impaired mortgage loans
Average balance impaired mortgage loans			$ 5	$ 6