Segment Information (Tables)

3 Months Ended

Mar. 31, 2018

Segment Reporting [Abstract]

Premium Income by Major Line of Business within Each Segment

Segment information is as follows:

	Three Months Ended March 31
	2018		2017
	(in millions of dollars)
Premium Income
Unum US
Group Disability
Group Long-term Disability	$	441.2	$	434.4
Group Short-term Disability	176.3		157.9
Group Life and Accidental Death & Dismemberment
Group Life	399.2		367.8
Accidental Death & Dismemberment	38.7		36.6
Supplemental and Voluntary
Individual Disability	104.9		107.0
Voluntary Benefits	229.8		215.2
Dental and Vision	48.7		41.5
	1,438.8		1,360.4
Unum UK
Group Long-term Disability	90.8		80.8
Group Life	28.6		24.8
Supplemental	20.2		15.7
	139.6		121.3
Colonial Life
Accident, Sickness, and Disability	231.3		219.1
Life	81.0		74.2
Cancer and Critical Illness	86.0		81.0
	398.3		374.3
Closed Block
Individual Disability	109.4		121.3
Long-term Care	161.3		163.1
All Other	2.6		2.5
	273.3		286.9
Total Premium Income	$	2,250.0	$	2,142.9

Selected Operating Statement Data by Segment

	Unum US		Unum UK		Colonial Life		Closed Block		Corporate			Total
	(in millions of dollars)
Three Months Ended March 31, 2018
Premium Income	$	1,438.8	$	139.6	$	398.3	$	273.3	$	—		$	2,250.0
Net Investment Income	194.2		27.6		37.3		337.7		5.5			602.3
Other Income	29.0		—		0.3		19.0		1.2			49.5
Adjusted Operating Revenue	$	1,662.0	$	167.2	$	435.9	$	630.0	$	6.7		$	2,901.8
Adjusted Operating Income (Loss)	$	243.9	$	29.8	$	81.0	$	28.9	$	(40.3	)	$	343.3
Three Months Ended March 31, 2017
Premium Income	$	1,360.4	$	121.3	$	374.3	$	286.9	$	—		$	2,142.9
Net Investment Income	202.5		26.6		35.1		335.3		2.9			602.4
Other Income	28.7		—		0.3		20.8		0.4			50.2
Adjusted Operating Revenue	$	1,591.6	$	147.9	$	409.7	$	643.0	$	3.3		$	2,795.5
Adjusted Operating Income (Loss)	$	239.1	$	26.6	$	82.4	$	31.6	$	(39.8	)	$	339.9

Assets by Segment

	March 31		December 31
	2018		2017
	(in millions of dollars)
Assets
Unum US	$	18,036.3	$	18,109.1
Unum UK	3,497.6		3,428.1
Colonial Life	4,292.9		4,184.1
Closed Block	34,603.8		35,051.2
Corporate	2,581.7		3,240.6
Total Assets	$	63,012.3	$	64,013.1

Reconciliation of Total Revenue and Income before Income Tax by Segment to Adjusted Operating Revenue and Adjusted Operating Income

A reconciliation of total revenue to "adjusted operating revenue" and income before income tax to "adjusted operating income" is as follows:

	Three Months Ended March 31
	2018			2017
	(in millions of dollars)
Total Revenue	$	2,899.6		$	2,806.5
Excluding:
Net Realized Investment Gain (Loss)	(2.2		)	11.0
Adjusted Operating Revenue	$	2,901.8		$	2,795.5
Income Before Income Tax	$	341.1		$	330.3
Excluding:
Net Realized Investment Gain (Loss)	(2.2		)	11.0
Loss from Guaranty Fund Assessment	—			(20.6		)
Adjusted Operating Income	$	343.3		$	339.9