Industry Segments

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

Industry Segments

Industry Segments

The Company’s reportable segments include the following two business segments, plus a corporate segment:

•Insurance - predominantly commercial insurance business, including excess and surplus lines, admitted lines and specialty personal lines throughout the United States, as well as insurance business in the United Kingdom, Continental Europe, South America, Canada, Mexico, Scandinavia, Asia and Australia.

•Reinsurance - reinsurance business on a facultative and treaty basis, primarily in the United States, United Kingdom, Continental Europe, Australia, the Asia-Pacific region and South Africa.

Commencing with the first quarter of 2017, the Company reclassified two businesses from the Insurance segment to the Reinsurance segment. Reclassifications have been made to the Company's prior periods financial information to conform with this presentation.

The accounting policies of the segments are the same as those described in the summary of significant accounting policies. Income tax expense and benefits are calculated based upon the Company’s overall effective tax rate.

Summary financial information about the Company’s reporting segments is presented in the following table. Income before income taxes by segment includes allocated investment income. Identifiable assets by segment are those assets used in or allocated to the operation of each segment.

	Revenues
(In thousands)	Earned Premiums		Investment Income		Other		Total (1)		Pre-Tax Income (Loss)			Net Income (Loss) to Common Stockholders
December 31, 2017
Insurance (2)	$	5,706,443	$	436,178	$	86,864	$	6,229,485	$	756,153		$	535,186
Reinsurance	604,976		91,146		—		696,122		(15,276		)	(5,131		)
Corporate, other and eliminations (3)	—		48,464		374,835		423,299		(303,965		)	(199,269		)
Net investment gains	—		—		335,858		335,858		335,858			218,308
Consolidated	$	6,311,419	$	575,788	$	797,557	$	7,684,764	$	772,770		$	549,094
December 31, 2016
Insurance	$	5,618,842	$	431,489	$	97,879	$	6,148,210	$	799,139		$	534,613
Reinsurance	674,506		102,617		—		777,123		98,277			68,400
Corporate, other and eliminations (3)	—		30,057		431,789		461,846		(267,983		)	(174,650		)
Net investment gains	—		—		267,005		267,005		267,005			173,553
Consolidated	$	6,293,348	$	564,163	$	796,673	$	7,654,184	$	896,438		$	601,916
December 31, 2015
Insurance	$	5,393,166	$	386,801	$	96,487	$	5,876,454	$	748,515		$	512,426
Reinsurance	647,443		97,882		—		745,325		122,930			86,487
Corporate, other and eliminations (3)	—		27,962		464,392		492,354		(231,739		)	(155,230		)
Net investment gains	—		—		92,324		92,324		92,324			60,011
Consolidated	$	6,040,609	$	512,645	$	653,203	$	7,206,457	$	732,030		$	503,694

Identifiable Assets
(In thousands)	December 31,
	2017		2016
Insurance	$	19,263,193	$	19,026,658
Reinsurance	3,169,731		2,635,438
Corporate, other and eliminations(2)	1,866,993		1,702,748
Consolidated	$	24,299,917	$	23,364,844

_______________________________________

(1) Revenues for Insurance includes $688.2 million, $733.3 million and $786.9 million in 2017, 2016 and 2015, respectively, from foreign countries. Revenues for Reinsurance includes $201.3 million, $200.5 million and $223.4 million in 2017, 2016 and 2015, respectively, from foreign countries.

(2) Net income (loss) to common stockholders for 2017 within the Insurance segment includes a net $21 million benefit related to tax reform.

(3) Corporate, other and eliminations represent corporate revenues and expenses and other items that are not allocated to business segments.

Net premiums earned by major line of business are as follows:

(In thousands)	2017		2016		2015
Insurance
Other liability	$	1,843,826	$	1,761,748	$	1,614,453
Workers' compensation	1,481,507		1,402,611		1,355,631
Short-tail lines	1,184,799		1,280,091		1,277,538
Commercial automobile	650,441		642,452		674,078
Professional liability	545,870		531,940		471,466
Total Insurance	5,706,443		5,618,842		5,393,166
Reinsurance
Casualty	377,650		405,470		438,800
Property	227,326		269,036		208,643
Total Reinsurance	604,976		674,506		647,443
Total	$	6,311,419	$	6,293,348	$	6,040,609