DAC and VOBA - Deferred Policy Acquisition Costs (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance at January 1	$ 335.0		$ 452.3
Deferrals of commission and expenses	55.5		57.1
Amortization:
Amortization	(59.6)		(53.3)
Interest accrued at 4% to 7%	22.9	[1]	24.2	[1]
Net amortization included in Condensed Consolidated Statement of Operations	(36.7)		(29.1)
Change in unrealized capital gains/losses on availabe-for-sale securities	(76.7)		(1.7)
Balance at June 30	$ 277.1		$ 478.6
Minimum
Amortization:
Deferred Policy Acquisition Costs, Interest Accrued Percentage	4.00%
Maximum
Amortization:
Deferred Policy Acquisition Costs, Interest Accrued Percentage			7.00%

[1] Interest accrued at 4.0% to 7.0% during 2012 and 2011.