Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2017	Jun. 16, 2017	Apr. 28, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term Debt	$ 46			$ 1,904
Unamortized debt issuance costs	6
Variable Interest Entity
Debt Instrument [Line Items]
Long-term Debt	$ 11			23
Surplus Note Due 2038
Debt Instrument [Line Items]
Debt instrument, stated interest rate	8.595%	8.595%
Long-term Debt	$ 0			744
Surplus Note Due 2032
Debt Instrument [Line Items]
Debt instrument, stated interest rate	5.13%		5.13%
Long-term Debt	$ 0			750
Surplus Note Due 2033
Debt Instrument [Line Items]
Debt instrument, stated interest rate	6.00%		6.00%
Long-term Debt	$ 0			350
Non-recourse Debt Due 2030
Debt Instrument [Line Items]
Debt instrument, stated interest rate	7.028%
Long-term Debt	$ 35			37
Long-term Debt Excluding CSEs
Debt Instrument [Line Items]
Long-term Debt	$ 35			$ 1,881