Reinsurance (Tables)

12 Months Ended

Dec. 31, 2015

Reinsurance Disclosures [Abstract]

Summary Of Direct, Assumed And Ceded Premiums Written And Earned

A summary of direct, assumed and ceded premiums written and earned for the years ended December 31 is as follows:

	2015						2014						2013
	Written			Earned			Written			Earned			Written			Earned
Direct	$	72,925.5		$	73,259.2		$	68,628.6		$	68,304.3		$	65,939.1		$	66,038.9
Assumed	221.8			221.9			192.3			194.0			174.3			174.0
Ceded	(95.8		)	(96.0		)	(108.5		)	(108.5		)	(92.6		)	(93.8		)
Net premiums	$	73,051.5		$	73,385.1		$	68,712.4		$	68,389.8		$	66,020.8		$	66,119.1
Percentage—assumed to net premiums	0.3		%	0.3		%	0.3		%	0.3		%	0.3		%	0.3		%

Summary Of Net Premiums Written And Earned By Segment

A summary of net premiums written and earned by segment (see Note 19, “Segment Information”) for the years ended December 31 is as follows:

	2015				2014				2013
	Written		Earned		Written		Earned		Written		Earned
Reportable segments:
Commercial and Specialty Business	$	33,016.9	$	33,078.0	$	35,084.7	$	35,045.2	$	35,733.9	$	35,772.0
Government Business	40,034.6		40,307.1		33,627.7		33,344.6		30,286.9		30,347.1
Other	—		—		—		—		—		—
Net premiums	$	73,051.5	$	73,385.1	$	68,712.4	$	68,389.8	$	66,020.8	$	66,119.1

Effect Of Reinsurance On Benefit Expense

The effect of reinsurance on benefit expense for the years ended December 31 is as follows:

	2015			2014			2013
Direct	$	61,674.0		$	57,496.6		$	56,185.2
Assumed	192.2			182.4			155.6
Ceded	(749.3		)	(824.1		)	(103.7		)
Net benefit expense	$	61,116.9		$	56,854.9		$	56,237.1

Effect Of Reinsurance On Certain Assets And Liabilities

The effect of reinsurance on certain assets and liabilities at December 31 is as follows:

	2015		2014
Policy liabilities, assumed	$	56.7	$	57.4
Unearned income, assumed	0.5		0.4
Premiums payable, ceded	9.3		7.7
Premiums receivable, assumed	23.2		5.4