CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 236.0	$ 203.8	$ 683.4	$ 641.0
Other Comprehensive Income (Loss)
Change in Net Unrealized Gain on Securities Before Adjustment (net of tax expense (benefit) of $113.9; $(89.6); $1,008.1; $(561.7))	277.2	(168.5)	1,999.2	(1,085.4)
Change in Adjustment to Deferred Acquisition Costs and Reserves for Future Policy and Contract Benefits, Net of Reinsurance (net of tax expense (benefit) of $(51.7); $113.9; $(707.0); $500.8)	(135.1)	215.0	(1,400.3)	953.7
Change in Net Gain on Cash Flow Hedges (net of tax expense (benefit) of $(4.3); $4.7; $(22.3); $7.5)	(8.4)	13.4	(42.8)	14.1
Change in Foreign Currency Translation Adjustment (net of tax benefit of $-; $-; $-; $0.1)	(25.8)	(44.1)	(131.6)	(33.2)
Change in Unrecognized Pension and Postretirement Benefit Costs (net of tax expense of $1.7; $1.4; $5.3; $3.3)	3.0	2.8	10.1	6.4
Total Other Comprehensive Income (Loss)	110.9	18.6	434.6	(144.4)
Comprehensive Income	$ 346.9	$ 222.4	$ 1,118.0	$ 496.6