Fair Value Measurements - Significant Unobservable Inputs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Actuarial Assumptions, Benefit Utilization, Percent of Policyholders Taking Systematic Withdrawals	31.00%		30.00%
Fair Value Inputs, Actuarial Assumptions, Benefit Utilization, Percent of Policyholders Assumed to Begin Systematic Withdrawals	85.00%		85.00%
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Average Expected Delay	2 years 2 months 12 days		2 years 3 months 18 days
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	$ 16,400.0		$ 16,500.0
Actuarial Assumptions, Lapses, threshold percentage	85.00%				85.00%
Actuarial Assumptions, Policyholder Deposits, threshold percentage	85.00%				85.00%
Stabilizer and MCGs
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Percentage of Plans	100.00%		100.00%
Stabilizer (Investment Only) and MCG Contracts
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Percentage of Plans	88.00%		88.00%
Stabilizer with Recordkeeping Agreements
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Percentage of Plans	12.00%		12.00%
Investment contract | GMWB/GMWBL | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	15.00%	[1]			15.00%
Interest rate implied volatility	0.20%	[1]			0.20%
Equity Funds	50.00%	[1]			50.00%
Equity and Fixed Income Funds	(38.00%)	[1]			(33.00%)
Interest Rates and Equity Funds	(31.00%)	[1]			(30.00%)
Nonperformance risk	(0.10%)	[1]			(0.10%)
Benefit Utilization	85.00%	[1],[2]			85.00%
Partial Withdrawals	0.00%	[1]			0.00%
Lapses	0.08%	[1],[3]			0.08%
Policyholder Deposits	0.00%	[1],[4]			0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1],[5]			0.00%
Investment contract | GMWB/GMWBL | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	25.00%	[1]			25.00%
Interest rate implied volatility	16.00%	[1]			16.00%
Equity Funds	98.00%	[1]			98.00%
Equity and Fixed Income Funds	62.00%	[1]			62.00%
Interest Rates and Equity Funds	(14.00%)	[1]			(14.00%)
Nonperformance risk	0.79%	[1]			0.79%
Benefit Utilization	100.00%	[1],[2]			100.00%
Partial Withdrawals	10.00%	[1]			10.00%
Lapses	40.00%	[1],[3]			40.00%
Policyholder Deposits	0.00%	[1],[4]			0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1],[5]			0.00%
Investment contract | GMAB | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	15.00%	[1]			15.00%
Interest rate implied volatility	0.20%	[1]			0.20%
Equity Funds	50.00%	[1]			50.00%
Equity and Fixed Income Funds	(38.00%)	[1]			(33.00%)
Interest Rates and Equity Funds	(31.00%)	[1]			(30.00%)
Nonperformance risk	0.10%	[1]			(0.10%)
Benefit Utilization	0.00%	[1]			0.00%
Partial Withdrawals	0.00%	[1]			0.00%
Lapses	0.08%	[1],[3]			0.08%
Policyholder Deposits	0.00%	[1],[4]			0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1],[5]			0.00%
Investment contract | GMAB | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	25.00%	[1]			25.00%
Interest rate implied volatility	16.00%	[1]			16.00%
Equity Funds	98.00%	[1]			98.00%
Equity and Fixed Income Funds	62.00%	[1]			62.00%
Interest Rates and Equity Funds	(14.00%)	[1]			(14.00%)
Nonperformance risk	0.79%	[1]			0.79%
Benefit Utilization	0.00%	[1]			0.00%
Partial Withdrawals	10.00%	[1]			10.00%
Lapses	31.00%	[1],[3]			31.00%
Policyholder Deposits	0.00%	[1],[4]			0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1],[5]			0.00%
Investment contract | FIA | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	0.00%	[1]			0.00%
Interest rate implied volatility	0.00%	[1]			0.00%
Equity Funds	0.00%	[1]			0.00%
Equity and Fixed Income Funds	0.00%	[1]			0.00%
Interest Rates and Equity Funds	0.00%	[1]			0.00%
Nonperformance risk	(0.10%)	[1]			(0.10%)
Benefit Utilization	0.00%	[1]			0.00%
Partial Withdrawals	0.00%	[1]			0.00%
Lapses	0.00%	[1],[3]			0.00%
Policyholder Deposits	0.00%	[1],[4]			0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1]			0.00%
Investment contract | FIA | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	0.00%	[1]			0.00%
Interest rate implied volatility	0.00%	[1]			0.00%
Equity Funds	0.00%	[1]			0.00%
Equity and Fixed Income Funds	0.00%	[1]			0.00%
Interest Rates and Equity Funds	0.00%	[1]			0.00%
Nonperformance risk	0.79%	[1]			0.79%
Benefit Utilization	0.00%	[1]			0.00%
Partial Withdrawals	0.00%	[1]			0.00%
Lapses	10.00%	[1],[3]			10.00%
Policyholder Deposits	0.00%	[1],[4]			0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1]			0.00%
Derivative Financial Instruments, Liabilities | Stabilizer and MCGs | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	0.00%	[1]			0.00%
Interest rate implied volatility	0.20%	[1]			0.20%
Equity Funds	0.00%	[1]			0.00%
Equity and Fixed Income Funds	0.00%	[1]			0.00%
Interest Rates and Equity Funds	0.00%	[1]			0.00%
Nonperformance risk	(0.10%)	[1]			(0.10%)
Benefit Utilization	0.00%	[1]			0.00%
Partial Withdrawals	0.00%	[1]			0.00%
Lapses	0.00%	[1],[6]			0.00%
Policyholder Deposits	0.00%	[1],[4],[6]			0.00%
Actuarial Assumptions, Lapses under percent threshold	0.00%				0.00%
Actuarial Assumptions, Policyholder Deposits under percent threshold	0.00%				0.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1]			0.00%
Derivative Financial Instruments, Liabilities | Stabilizer and MCGs | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Long-term equity implied volatility	0.00%	[1]			0.00%
Interest rate implied volatility	7.60%	[1]			8.00%
Equity Funds	0.00%	[1]			0.00%
Equity and Fixed Income Funds	0.00%	[1]			0.00%
Interest Rates and Equity Funds	0.00%	[1]			0.00%
Nonperformance risk	0.79%	[1]			0.79%
Benefit Utilization	0.00%	[1]			0.00%
Partial Withdrawals	0.00%	[1]			0.00%
Lapses	55.00%	[1],[6]			55.00%
Policyholder Deposits	60.00%	[1],[4],[6]			60.00%
Actuarial Assumptions, Lapses under percent threshold	25.00%				25.00%
Actuarial Assumptions, Policyholder Deposits under percent threshold	30.00%				30.00%
Fair Value Inputs, Actuarial Assumptions, Mortality	0.00%	[1]			0.00%
Derivative Financial Instruments, Liabilities | Stabilizer (Investment Only) and MCG Contracts | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	0.00%				0.00%
Policyholder Deposits	0.00%				0.00%
Actuarial Assumptions, Lapses under percent threshold	0.00%				0.00%
Actuarial Assumptions, Policyholder Deposits under percent threshold	0.00%				0.00%
Derivative Financial Instruments, Liabilities | Stabilizer (Investment Only) and MCG Contracts | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	30.00%				30.00%
Policyholder Deposits	55.00%				55.00%
Actuarial Assumptions, Lapses under percent threshold	15.00%				15.00%
Actuarial Assumptions, Policyholder Deposits under percent threshold	15.00%				15.00%
Derivative Financial Instruments, Liabilities | Stabilizer with Recordkeeping Agreements | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	0.00%				0.00%
Policyholder Deposits	0.00%				0.00%
Actuarial Assumptions, Lapses under percent threshold	0.00%				0.00%
Actuarial Assumptions, Policyholder Deposits under percent threshold	0.00%				0.00%
Derivative Financial Instruments, Liabilities | Stabilizer with Recordkeeping Agreements | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	55.00%				55.00%
Policyholder Deposits	60.00%				60.00%
Actuarial Assumptions, Lapses under percent threshold	25.00%				25.00%
Actuarial Assumptions, Policyholder Deposits under percent threshold	30.00%				30.00%
In the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	12,400.0		11,200.0
In the Money | During Surrender Charge Period | GMWB/GMWBL
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	6,200.0	[7]	5,700.0	[6]
In the Money | During Surrender Charge Period | GMWB/GMWBL | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	0.08%				0.08%
In the Money | During Surrender Charge Period | GMWB/GMWBL | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	5.50%				5.50%
In the Money | During Surrender Charge Period | GMAB
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	0	[7],[8]	0	[6],[8]
In the Money | During Surrender Charge Period | GMAB | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	0.08%				0.08%
In the Money | During Surrender Charge Period | GMAB | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	8.20%				8.20%
In the Money | After Surrender Charge Period | GMWB/GMWBL
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	6,200.0	[7]	5,600.0	[6]
In the Money | After Surrender Charge Period | GMWB/GMWBL | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	1.50%				1.50%
In the Money | After Surrender Charge Period | GMWB/GMWBL | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	21.00%				21.00%
In the Money | After Surrender Charge Period | GMAB
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	0	[7],[8]	0	[6],[8]
In the Money | After Surrender Charge Period | GMAB | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	2.50%				2.50%
In the Money | After Surrender Charge Period | GMAB | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	21.00%				21.00%
Out of the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	4,000.0		5,300.0
Out of the Money | During Surrender Charge Period | GMWB/GMWBL
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	2,500.0		3,300.0
Out of the Money | During Surrender Charge Period | GMWB/GMWBL | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	0.36%				0.36%
Out of the Money | During Surrender Charge Period | GMWB/GMWBL | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	11.00%				11.00%
Out of the Money | During Surrender Charge Period | GMAB
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	0	[8]	0	[8]
Out of the Money | During Surrender Charge Period | GMAB | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	0.41%				0.41%
Out of the Money | During Surrender Charge Period | GMAB | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	12.00%				12.00%
Out of the Money | After Surrender Charge Period | GMWB/GMWBL
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	2,200.0		2,800.0
Out of the Money | After Surrender Charge Period | GMWB/GMWBL | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	6.90%				6.90%
Out of the Money | After Surrender Charge Period | GMWB/GMWBL | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	40.00%				40.00%
Out of the Money | After Surrender Charge Period | GMAB
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	0.1		100.0
Out of the Money | After Surrender Charge Period | GMAB | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	12.00%				12.00%
Out of the Money | After Surrender Charge Period | GMAB | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Lapses	31.00%				31.00%
Age 60 and under
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Average Expected Delay	5 years 4 months 24 days		5 years 4 months 24 days
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	3,400.0		3,500.0
Age 60 and under | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Attained Age	0				0
Age 60 and under | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Attained Age	60				60
Age 60 and under | In the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	2,400.0		2,100.0
Age 60 and under | Out of the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	1,000.0		1,400.0
Age 60-69
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Average Expected Delay	1 year 2 months 12 days		1 year 4 months 24 days
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	7,500.0		7,700.0
Age 60-69 | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Attained Age	60				60
Age 60-69 | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Attained Age	69				69
Age 60-69 | In the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	5,600.0		5,100.0
Age 60-69 | Out of the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	1,900.0		2,600.0
Age 70 and over
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Average Expected Delay	0 days		0 years
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	5,500.0		5,300.0
Age 70 and over | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Attained Age	70				70
Age 70 and over | In the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	4,400.0		4,000.0
Age 70 and over | Out of the Money
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	$ 1,100.0		$ 1,300.0

[1] Represents the range of reasonable assumptions that management has used in its fair value calculations.

[2] Those policyholders who have elected systematic withdrawals are assumed to continue taking withdrawals. As a percent of account value, 31% are taking systematic withdrawals. Of those policyholders who are not taking withdrawals, we assume that 85% will begin systematic withdrawals after a delay period. The utilization function varies by policyholder age and policy duration. Interactions with lapse and mortality also affect utilization. The utilization rate for GMWB and GMWBL tends to be lower for younger contract owners and contracts that have not reached their maximum accumulated GMWB and GMWBL benefit amount. There is also a lower utilization rate, though indirectly, for contracts that are less "in the money" (i.e., where the notional benefit amount is in excess of the account value) due to higher lapses. Conversely, the utilization rate tends to be higher for contract owners near or beyond retirement age and contracts that have accumulated their maximum GMWB or GMWBL benefit amount. There is also a higher utilization rate, though indirectly, for contracts which are highly "in the money". The chart below provides the GMWBL account value by current age group and average expected delay times from the associated attained age group as of March 31, 2014 (account value amounts are in $ billions). Account Values Attained Age Group In the Money Out of the Money Total Average Expected Delay (Years)< 60 $2.4 $1.0 $3.4 5.460-69 5.6 1.9 7.5 1.270+ 4.4 1.1 5.5 0.0 $12.4 $4.0 $16.4 2.2

[3] Lapse rates tend to be lower during the contractual surrender charge period and higher after the surrender charge period ends; the highest lapse rates occur in the year immediately after the end of the surrender charge period. The Company makes dynamic adjustments to lower the lapse rates for contracts that are more "in the money." The table below shows an analysis of policy account values according to whether they are in or out of the surrender charge period and to whether they are "in the money" or "out of the money" as of March 31, 2014 (account value amounts are in $ billions). GMAB GMWB/GMWBL Moneyness Account Value Lapse Range Account Value Lapse RangeDuring Surrender Charge Period In the Money** $—*0.08% to 8.2% $6.2 0.08% to 5.5% Out of the Money —*0.41% to 12% 2.5 0.36% to 11%After Surrender Charge Period In the Money** $—*2.5% to 21% $6.2 1.5% to 21% Out of the Money 0.1 12% to 31% 2.2 6.9% to 40%* Less than $0.1.** The low end of the range corresponds to policies that are highly "in the money." The high end of the range corresponds to the policies that are close to zero in terms of "in the moneyness."

[4] Measured as a percentage of assets under management or assets under administration.

[5] The mortality rate is based on the Annuity 2000 Basic table with mortality improvements.

[6] Stabilizer contracts with recordkeeping agreements have a different range of lapse and policyholder deposit assumptions from Stabilizer (Investment only) and MCG contracts as shown below: Percentage of Plans Overall Range of Lapse Rates Range of Lapse Rates for 85% of Plans Overall Range of Policyholder Deposits Range of Policyholder Deposits for 85% of PlansStabilizer (Investment Only) and MCG Contracts88% 0-30% 0-15% 0-55% 0-15%Stabilizer with Recordkeeping Agreements12% 0-55% 0-25% 0-60% 0-30%Aggregate of all plans100% 0-55% 0-25% 0-60% 0-30%

[7] The low end of the range corresponds to policies that are highly "in the money." The high end of the range corresponds to the policies that are close to zero in terms of "in the moneyness."

[8] * Less than $0.1