Current weighted average loan to value ratio of commercial mortgage loan.

No definition available.

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- Definition

Original weighted average loan to value ratio of commercial mortgage loan.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that have been derecognized. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
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-Paragraph 4
-Subparagraph (a)(2)
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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 40
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- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
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- Definition

The carrying amount of the outstanding balance due under the mortgage loan.

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- Definition

Amount of principal due on loans that have been delinquent, which may exclude loans having interest delinquent for three months or less, as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that continue to be recognized in the statement of financial position. Includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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- Definition

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Investments - Investments - Mortgage Loans- Valuation Allowance Activity (Details) - USD ($)	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 3,355,000,000		$ 3,175,000,000
Current Weighted Average Loan to Value Ratio of Commercial Mortgage Loan	51.00%
Original Weighted Average Loan to Value Ratio of Commercial Mortgage loan	62.00%
Servicing rights	$ 0		0
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	(1,000,000)	$ 0
(Additions)/Reversals	0	0
Deductions	0	0
Ending balance	(1,000,000)	$ 0
Mortgage Loans on Real Estate, Other Additions	0
Held-for-sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	0		0
Allowance for Loan and Lease Losses [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	24,000,000		0
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans on Real Estate	3,400,000,000		3,200,000,000
Mortgage loans	3,355,000,000		3,175,000,000
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	(1,000,000)
Mortgage loans \| Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans past due by 90 days or more	0
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans serviced	5,700,000,000		1,300,000,000
Loans serviced on behalf of third parties	3,500,000,000		402,000,000
Commercial Loan [Member] \| Investments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans serviced on behalf of third parties, retained and reported as assets			566,000,000
Commercial Loan [Member] \| Investments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans serviced on behalf of third parties, retained and reported as assets	$ 2,200,000,000
Commercial Loan [Member] \| Assets Held for Sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans serviced on behalf of third parties, retained and reported as assets			356,000,000
Mortgage loans \| Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans past due by 90 days or more			$ 0