Fair Value (Quantitative Information) (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Interest rate contracts [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Swap yield	2.42%	2.48%
Interest rate contracts [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Swap yield	0.00%	4.50%
Foreign currency exchange rate contracts [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Swap yield	0.57%	0.97%
Correlation	39.00%	38.00%
Foreign currency exchange rate contracts [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Swap yield	0.00%	7.67%
Correlation	47.00%	47.00%
Credit contracts [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit spreads	0.98%	0.98%
Credit contracts [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit spreads	0.00%	1.01%
Equity market contracts [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Correlation	60.00%	60.00%
Volatility	13.00%	13.00%
Equity market contracts [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Correlation	60.00%	60.00%
Volatility	28.00%	28.00%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Income Approach Valuation Technique [Member] | Durations 1-10 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Lapse Rate, Low End	0.50%	0.50%
Lapse Rate, High End	100.00%	100.00%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Income Approach Valuation Technique [Member] | Durations 11-20 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Lapse Rate, Low End	2.00%	2.00%
Lapse Rate, High End	100.00%	100.00%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Income Approach Valuation Technique [Member] | Durations 21-116 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Lapse Rate, Low End	2.00%	2.00%
Lapse Rate, High End	100.00%	100.00%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Income Approach Valuation Technique [Member] | Ages 0-40 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortality Rate, Low End	0.00%	0.00%
Mortality Rate, High End	0.28%	0.14%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Income Approach Valuation Technique [Member] | Ages 41-60 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortality Rate, Low End	0.04%	0.04%
Mortality Rate, High End	0.88%	0.88%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Income Approach Valuation Technique [Member] | Ages 61-115 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortality Rate, Low End	0.26%	0.26%
Mortality Rate, High End	100.00%	100.00%
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Utilization rates	20.00%	20.00%
Withdrawal rates	0.00%	0.00%
Long-term equity volatilities	15.86%	9.14%
Nonperformance risk spread	(0.28%)	(1.08%)
Embedded derivatives direct and assumed guaranteed minimum benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Utilization rates	50.00%	50.00%
Withdrawal rates	40.00%	40.00%
Long-term equity volatilities	40.00%	40.00%
Nonperformance risk spread	0.90%	0.83%
U.S. corporate and foreign corporate securities [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Delta spread adjustments	(0.05%)	(0.10%)
Illiquidity premium	0.30%	0.30%
Offered quotes	$ 31	$ 33
Quoted prices	$ 0
Matrix Pricing - Offered quotes	$ 0	$ 4
Credit spreads	(14.85%)	(14.89%)
U.S. corporate and foreign corporate securities [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Delta spread adjustments	2.50%	2.40%
Illiquidity premium	0.30%	0.30%
Offered quotes	$ 1,250	$ 145
Quoted prices	$ 286
Matrix Pricing - Offered quotes	$ 127	$ 145
Credit spreads	7.87%	8.76%
U.S. corporate and foreign corporate securities [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Delta spread adjustments	0.48%	0.46%
Illiquidity premium	0.30%	0.30%
Offered quotes	$ 239	$ 95
Quoted prices	$ 110
Matrix Pricing - Offered quotes	$ 101	$ 100
Credit spreads	1.91%	1.74%
Foreign government debt securities [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 66	$ 84
Quoted prices	$ 64	$ 64
Credit spreads	0.10%	0.04%
Foreign government debt securities [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 157	$ 156
Quoted prices	$ 906	$ 156
Credit spreads	1.05%	0.72%
Foreign government debt securities [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 110	$ 107
Quoted prices	$ 140	$ 100
Credit spreads	0.25%	0.32%
RMBS [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 2	$ 69
Quoted prices	$ 0	$ 10
Credit spreads	(1.41%)	(1.36%)
RMBS [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 110	$ 101
Quoted prices	$ 120	$ 109
Credit spreads	12.34%	36.09%
RMBS [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 90	$ 93
Quoted prices	$ 96	$ 98
Credit spreads	2.52%	2.88%
CMBS [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 13	$ 90
Quoted prices	$ 1	$ 70
Credit spreads	3.50%	2.15%
CMBS [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 100	$ 101
Quoted prices	$ 112	$ 104
Credit spreads	3.50%	20.25%
CMBS [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 100	$ 95
Quoted prices	$ 97	$ 97
Credit spreads	3.50%	4.09%
ABS [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 0	$ 56
Quoted prices	$ 0	$ 0
Credit spreads	1.31%	0.30%
ABS [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 106	$ 106
Quoted prices	$ 107	$ 110
Credit spreads	18.79%	18.78%
ABS [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Offered quotes	$ 98	$ 98
Quoted prices	$ 101	$ 101
Credit spreads	2.25%	1.45%