Fair Value of Financial Instruments (Fair Value Inputs Quantitative Information) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	221,209	$ 204,615
Liabilities Fair Value Disclosure [Abstract]
Liabilities measured at fair value	(3,517)	(2,308)
Significant Unobservable Inputs (Level 3) [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	4,149	3,815
Liabilities Fair Value Disclosure [Abstract]
Liabilities measured at fair value	(1,602)	(85)
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Corporate bonds [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	1,262
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Asset-backed Securities [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	64
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Foreign government bonds [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	80
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Hybrid and redeemable preferred securities [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	20
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Equity securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	27
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Other assets - reinsurance recoverable [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure	154
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Indexed annuity and IUL contracts embedded derivatives [Member] | Future contract benefits [Member]
Liabilities Fair Value Disclosure [Abstract]
Liabilities measured at fair value	(1,170)
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | GLB Embedded Derivative Reserves [Member]
Liabilities Fair Value Disclosure [Abstract]
Liabilities measured at fair value	(174)
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Corporate bonds [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	0.50%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Asset-backed Securities [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	2.80%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Foreign government bonds [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	2.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Hybrid and redeemable preferred securities [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	2.10%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Equity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	4.30%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Other assets - reinsurance recoverable [Member]
Fair Value Inputs [Abstract]
Lapse rate	1.00%
Utilization of guaranteed withdrawal	90.00%
Claims utilization factor	60.00%
Premiums utilization Factor	70.00%
NPR	0.00%
Volatility	1.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | Indexed annuity and IUL contracts embedded derivatives [Member] | Future contract benefits [Member]
Fair Value Inputs [Abstract]
Lapse rate	1.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Minimum [Member] | GLB Embedded Derivative Reserves [Member]
Fair Value Inputs [Abstract]
Lapse rate	1.00%
Utilization of guaranteed withdrawal	90.00%
Claims utilization factor	60.00%
Premiums utilization Factor	70.00%
NPR	0.00%
Volatility	1.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Corporate bonds [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	11.60%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Asset-backed Securities [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	3.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Foreign government bonds [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	3.50%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Hybrid and redeemable preferred securities [Member] | Fixed maturity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	2.10%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Equity securities [Member]
Assets Fair Value Disclosure [Abstract]
Liquidity Duration Adjustment	7.30%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Other assets - reinsurance recoverable [Member]
Fair Value Inputs [Abstract]
Lapse rate	30.00%
Utilization of guaranteed withdrawal	100.00%
Claims utilization factor	100.00%
Premiums utilization Factor	140.00%
NPR	0.35%
Volatility	28.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | Indexed annuity and IUL contracts embedded derivatives [Member] | Future contract benefits [Member]
Fair Value Inputs [Abstract]
Lapse rate	15.00%
Significant Unobservable Inputs (Level 3) [Member] | Discounted Cash Flow Valuation Technique [Member] | Maximum [Member] | GLB Embedded Derivative Reserves [Member]
Fair Value Inputs [Abstract]
Lapse rate	30.00%
Utilization of guaranteed withdrawal	100.00%
Claims utilization factor	100.00%
Premiums utilization Factor	140.00%
NPR	0.35%
Volatility	28.00%