Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Company-held mortgage loans held-for-investment, net
Commercial Mortgage Loans	$ 8,378	$ 7,233
Percentage of loans receivable on commercial mortgage loans	64.80%	67.90%
Agricultural Mortgage Loans	$ 2,694	$ 2,200
Percentage of loans receivable on agricultural mortgage loans	20.80%	20.70%
Residential Mortgage Loans	$ 1,824	$ 1,138
Percentage of loans receivable on residential mortgage loans	14.10%	10.70%
Subtotal	$ 12,896	$ 10,571
Percentage of loans receivable on subtotal	99.70%	99.30%
Valuation allowances	$ (55)	$ (46)
Percentage of loans receivable on valuation allowances	(0.40%)	(0.40%)
Subtotal mortgage loans, net	$ 12,841	$ 10,525
Percentage of loans receivable on subtotal mortgage loans held-for-investment, net	99.30%	98.90%
Mortgage Loans on Real Estate, Commerical and Consumer Net	$ 12,934	$ 10,640
Percentage of loans receivable on commercial mortgage loans held by consolidated securitization entities - fair value option	0.70%	1.10%
Percentage of loans held for sale on total mortgage loans, net	100.00%	100.00%
Variable Interest Entity, Primary Beneficiary
Company-held mortgage loans held-for-investment, net
Mortgage Loans on Real Estate, Commerical and Consumer Net	$ 93	$ 115

The balance represents the amount of loans that are secured by real estate mortgages.

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Percentage of Allowance For Loan And Lease Losses on Real Estate to total Mortgage Loans on Real Estate.

+ References

No definition available.

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- Definition

Percentage of Commercial Mortgage Loans Held By Consolidated Securitization Entities Fair Value Option to total Mortgage Loans on Real Estate.

+ References

No definition available.

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- Definition

Percentage of Consumer Mortgage Loans and Leases Receivable to total Mortgage Loans on Real Estate.

+ References

No definition available.

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- Definition

Percentage of Commercial Agricultural Loans Receivable to total Mortgage Loans on Real Estate.

+ References

No definition available.

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- Definition

Percentage of Commercial Mortgage Loans Receivable to total Mortgage Loans on Real Estate.

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No definition available.

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- Definition

Percentage of Mortgage Loans Held-for-investment, net to total Mortgage Loans on Real Estate.

+ References

No definition available.

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Percentage of Mortgage Loans Held For Investment to total Mortgage Loans on Real Estate.

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No definition available.

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- Definition

Percentage of Mortgage Loans On Real Estate to total Mortgage Loans on Real Estate.

+ References

No definition available.

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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

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-Publisher FASB
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-SubTopic 310
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- Definition

Amount before allowance of consumer mortgage. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes subordinated loans such as home equity lines of credit and loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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Amount before allowance of loans issued to agricultural institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

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Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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-Publisher FASB
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