Segment Information (Reconciliation Of Revenue From Reportable Segments To The Consolidated Statements Of Income) (Details) (USD $) In Millions, unless otherwise specified	3 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	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting [Abstract]
Reportable segments operating revenues									$ 70,191.4	$ 60,514.0	$ 59,865.2
Net investment income									659.1	686.1	703.7
Net realized gains on investments									271.9	334.9	235.1
Other-than-temporary impairment losses recognized in income									(98.9)	(37.8)	(93.3)
Total revenues	$ 17,901.7	$ 17,855.5	$ 17,690.3	$ 17,576.0	$ 15,438.3	$ 15,247.4	$ 15,396.3	$ 15,415.2	$ 71,023.5	$ 61,497.2	$ 60,710.7