Income Taxes Allocation of Income Tax (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended									6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013		Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2013	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (5.5)	$ 2.6	$ (16.9)	$ (1.9)	[1]	$ (7.4)	$ 4.3	$ 0.5	$ 18.8	$ (18.8)	$ (16.2)	$ (21.7)	$ 16.2	$ (6.3)
Income tax from OCI:
Unrealized investment (gains) losses												(11.8)	24.9	4.2
Pension												0	0	0
Policy dividend obligation and deferred policy acquisition cost												0	0	0
Other												0	0	0
Income tax related to cumulative effect of change in accounting												0	0	0
Total income tax recorded to all components of income												$ (33.5)	$ 41.1	$ (2.1)

[1] Results for the quarter ended March 31, 2013 include $3.2 million of income (loss) related to out of period adjustments. Such amounts are not material to any period presented.