CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net Income	$ 242.5	$ 218.6	$ 471.4	$ 431.2
Other Comprehensive Income (Loss)
Change in Net Unrealized Gain on Securities Before Adjustment (net of tax expense (benefit) of $304.7; $(734.6); $675.8; $(894.0))	572.7	(1,425.1)	1,282.7	(1,703.6)
Change in Adjustment to Deferred Acquisition Costs and Reserves for Future Policy and Contract Benefits, Net of Reinsurance (net of tax expense (benefit) of $(211.7); $500.4; $(483.7); $609.0)	(396.8)	928.3	(917.2)	1,125.7
Change in Net Gain on Cash Flow Hedges (net of tax expense (benefit) of $(11.8); $3.5; $(10.8); $3.3)	(28.5)	5.9	(26.8)	3.9
Change in Foreign Currency Translation Adjustment	30.2	0.9	37.8	(69.0)
Change in Unrecognized Pension and Postretirement Benefit Costs (net of tax expense of $0.0: $118.9; $0.3; $124.4)	(0.1)	221.0	0.4	231.7
Total Other Comprehensive Income (Loss)	177.5	(269.0)	376.9	(411.3)
Comprehensive Income (Loss)	$ 420.0	$ (50.4)	$ 848.3	$ 19.9