Income Taxes, Summary of Loss and Tax Credit Carryforwards (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Tax Effected	$ 18	$ 12
Capital loss carryforwards, Valuation Allowance, Tax Effected	12	9
Total loss carryforwards, Tax Effected	18
Tax credit carryforwards, Tax Effected	6	$ 6
Tax credit carryforwards, Valuation Allowances Tax Effected	4
Federal [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	33
Capital loss carryforwards, Tax Effected	11
Capital loss carryforwards, Valuation Allowance, Gross	5
Capital loss carryforwards, Valuation Allowance, Tax Effected	$ 2
Federal [Member] | Minimum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2026
Federal [Member] | Maximum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2035
Foreign [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	$ 14
Capital loss carryforwards, Tax Effected	3
Capital loss carryforwards, Valuation Allowance, Gross	3
Capital loss carryforwards, Valuation Allowance, Tax Effected	1
Tax credit carryforwards, Tax Effected	1
Tax credit carryforwards, Gross	1
Tax credit carryforwards, Valuation Allowances Gross	0
Tax credit carryforwards, Valuation Allowances Tax Effected	0
State [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	136
Capital loss carryforwards, Tax Effected	2
Capital loss carryforwards, Valuation Allowance, Gross	47
Capital loss carryforwards, Valuation Allowance, Tax Effected	1
Tax credit carryforwards, Tax Effected	5
Tax credit carryforwards, Gross	7
Tax credit carryforwards, Valuation Allowances Gross	7
Tax credit carryforwards, Valuation Allowances Tax Effected	$ 4
State [Member] | Minimum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2017
Tax credit carryforwards, Expiration Periods	2017
State [Member] | Maximum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2036
Tax credit carryforwards, Expiration Periods	2031
Capital Loss Carryforwards [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	$ 6
Capital loss carryforwards, Tax Effected	2
Capital loss carryforwards, Valuation Allowance, Gross	6
Capital loss carryforwards, Valuation Allowance, Tax Effected	$ 2
Capital Loss Carryforwards [Member] | Minimum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2017
Capital Loss Carryforwards [Member] | Maximum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2021