Separate Accounts, Death Benefits and Other Insurance Benefit Features and Embedded Product Derivatives Variable Annuity GMDB Benefits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Net Amount at Risk by Product and Guarantee [Line Items]
Account Value	$ 2,192.4		$ 2,232.4
NAR after Reinsurance	13.7		34.9
Average Attained Age of Annuitant	64 years		64 years
Less: General account value with GMDB	294.7		311.3
Subtotal separate account liabilities with GMDB	1,897.7		1,921.1
Separate account liabilities without GMDB	155.0		140.7
Total separate account liabilities	2,052.7		2,061.8
GMIB ending balance	385.7	[1]	403.3	[1]
Return of premium
Net Amount at Risk by Product and Guarantee [Line Items]
Account Value	728.8		755.9
NAR after Reinsurance	1.8		5.7
Average Attained Age of Annuitant	63 years		62 years
Step up
Net Amount at Risk by Product and Guarantee [Line Items]
Account Value	1,401.0		1,412.4
NAR after Reinsurance	7.0		21.7
Average Attained Age of Annuitant	63 years		62 years
Earnings enhancement benefit ("EEB")
Net Amount at Risk by Product and Guarantee [Line Items]
Account Value	35.9		37.4
NAR after Reinsurance	0.1		0.1
Average Attained Age of Annuitant	64 years		63 years
Greater of annual step up and roll up
Net Amount at Risk by Product and Guarantee [Line Items]
Account Value	26.7		26.7
NAR after Reinsurance	$ 4.8		$ 7.4
Average Attained Age of Annuitant	68 years		67 years

[1] Policies with a GMIB also have a GMDB, however these benefits are not additive. When a policy terminates due to death, any NAR related to GMIB is released. Similarly, when a policy goes into benefit status on a GMIB, its GMDB NAR is released.