CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net Income	$ 221.1	$ 205.7	$ 692.5	$ 636.9
Other Comprehensive Income (Loss)
Change in Net Unrealized Gain on Securities Before Adjustment (net of tax expense (benefit) of $(91.9); $(89.8); $583.9; $(983.8))	(152.2)	(151.3)	1,130.5	(1,854.9)
Change in Adjustment to Deferred Acquisition Costs and Reserves for Future Policy and Contract Benefits, Net of Reinsurance (net of tax expense (benefit) of $67.2; $169.8; $(416.5); $778.8)	113.0	283.1	(804.2)	1,408.8
Change in Net Gain on Cash Flow Hedges (net of tax expense (benefit) of $5.4; $(5.2); $(5.4); $(1.9))	14.0	(8.3)	(12.8)	(4.4)
Change in Foreign Currency Translation Adjustment	(60.2)	68.2	(22.4)	(0.8)
Change in Unrecognized Pension and Postretirement Benefit Costs (net of tax expense of $0.9; $0.5; $1.2; $124.9)	2.1	1.2	2.5	232.9
Total Other Comprehensive Income (Loss)	(83.3)	192.9	293.6	(218.4)
Comprehensive Income	$ 137.8	$ 398.6	$ 986.1	$ 418.5