Separate Accounts, Death Benefits and Other Insurance Benefit Features and Embedded Product Derivatives Changes in Guaranteed Liability Balances (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Variable Annuity GMDB
Movement in Guaranteed Benefit Liability, Gross [Roll Forward]
Liability balance, beginning of the period	$ 10.8	$ 10.8	$ 11.2
Incurred	2.0	1.0	1.5
Paid	(2.7)	(1.0)	(1.9)
Change due to net unrealized gains or losses included in AOCI	0	0	0
Assumption unlocking	6.9	0	0
Liability balance, end of the period	17.0	10.8	10.8
Variable Annuity GMIB
Movement in Guaranteed Benefit Liability, Gross [Roll Forward]
Liability balance, beginning of the period	20.9	17.0	17.3
Incurred	(3.4)	3.8	(0.7)
Paid	0	0	0
Change due to net unrealized gains or losses included in AOCI	(0.1)	0.3	0
Assumption unlocking	(7.9)	(0.2)	0.4
Liability balance, end of the period	9.5	20.9	17.0
Fixed Indexed Annuity GMWB & GMDB
Movement in Guaranteed Benefit Liability, Gross [Roll Forward]
Liability balance, beginning of the period	103.6	5.6	0.5
Incurred	62.5	40.1	5.1
Paid	(0.3)	0	0
Change due to net unrealized gains or losses included in AOCI	(57.1)	57.9	0
Assumption unlocking	(18.7)	0	0
Liability balance, end of the period	90.0	103.6	5.6
Universal Life
Movement in Guaranteed Benefit Liability, Gross [Roll Forward]
Liability balance, beginning of the period	115.8	100.6	89.9
Incurred	43.3	22.6	16.0
Paid	(14.3)	(9.5)	(6.3)
Change due to net unrealized gains or losses included in AOCI	(2.2)	2.1	1.0
Assumption unlocking	10.6	0	0
Liability balance, end of the period	$ 153.2	$ 115.8	$ 100.6