Segment Information (Tables)

6 Months Ended

Jun. 30, 2015

Segment Reporting [Abstract]

Summary of segment results

The following tables provide a summary of the segment results:

Three Months Ended June 30, 2015	North American  Insurance			Global Markets Insurance			Reinsurance			Total
Gross premiums written	$	517,483		$	134,997		$	173,490		$	825,970
Net premiums written	372,193			69,260			162,216			603,669
Net premiums earned	328,541			102,626			215,209			646,376
Net losses and loss expenses	(237,747		)	(65,754		)	(128,020		)	(431,521		)
Acquisition costs	(34,201		)	(24,337		)	(42,080		)	(100,618		)
General and administrative expenses	(58,144		)	(30,724		)	(19,495		)	(108,363		)
Underwriting (loss) income	(1,551		)	(18,189		)	25,614			5,874
Other insurance-related income	924			—			—			924
Other insurance-related expenses	(591		)	(644		)	—			(1,235		)
Segment (loss) income	(1,218		)	(18,833		)	25,614			5,563
Net investment income										42,760
Net realized investment losses										(20,182		)
Amortization of intangible assets										(2,819		)
Interest expense										(14,466		)
Foreign exchange loss										(1,265		)
Income before income taxes										$	9,591
Loss and loss expense ratio	72.4		%	64.1		%	59.5		%	66.8		%
Acquisition cost ratio	10.4		%	23.7		%	19.6		%	15.6		%
General and administrative expense ratio	17.7		%	29.9		%	9.1		%	16.8		%
Expense ratio	28.1		%	53.6		%	28.7		%	32.4		%
Combined ratio	100.5		%	117.7		%	88.2		%	99.2		%

Three Months Ended June 30, 2014	North American  Insurance			Global Markets Insurance			Reinsurance			Total
Gross premiums written	$	472,340		$	73,564		$	214,501		$	760,405
Net premiums written	293,388			50,733			209,803			553,924
Net premiums earned	265,800			37,998			233,449			537,247
Net losses and loss expenses	(178,732		)	(2,673		)	(133,450		)	(314,855		)
Acquisition costs	(25,829		)	(4,423		)	(44,027		)	(74,279		)
General and administrative expenses	(58,527		)	(17,477		)	(20,184		)	(96,188		)
Underwriting income	2,712			13,425			35,788			51,925
Other insurance-related income	—			—			—			—
Other insurance-related expenses	—			—			—			—
Segment income	2,712			13,425			35,788			51,925
Net investment income										36,793
Net realized investment gains										85,217
Amortization of intangible assets										(634		)
Interest expense										(14,592		)
Foreign exchange loss										(651		)
Income before income taxes										$	158,058
Loss and loss expense ratio	67.2		%	7.0		%	57.2		%	58.6		%
Acquisition cost ratio	9.7		%	11.6		%	18.9		%	13.8		%
General and administrative expense ratio	22.0		%	46.0		%	8.6		%	17.9		%
Expense ratio	31.7		%	57.6		%	27.5		%	31.7		%
Combined ratio	98.9		%	64.6		%	84.7		%	90.3		%

Six Months Ended June 30, 2015	North American  Insurance			Global Markets Insurance			Reinsurance			Total
Gross premiums written	$	898,249		$	195,559		$	612,776		$	1,706,584
Net premiums written	669,075			112,155			594,967			1,376,197
Net premiums earned	641,511			152,666			420,747			1,214,924
Net losses and loss expenses	(433,226		)	(86,264		)	(237,207		)	(756,697		)
Acquisition costs	(65,233		)	(31,345		)	(82,739		)	(179,317		)
General and administrative expenses	(117,432		)	(48,749		)	(39,320		)	(205,501		)
Underwriting (loss) income	25,620			(13,692		)	61,481			73,409
Other insurance-related income	1,778			—			—			1,778
Other insurance-related expenses	(1,445		)	(1,613		)	—			(3,058		)
Segment income	25,953			(15,305		)	61,481			72,129
Net investment income										87,311
Net realized investment gains										24,843
Amortization of intangible assets										(3,452		)
Interest expense										(28,803		)
Foreign exchange loss										(11,162		)
Income before income taxes										$	140,866
Loss and loss expense ratio	67.5		%	56.5		%	56.4		%	62.3		%
Acquisition cost ratio	10.2		%	20.5		%	19.7		%	14.8		%
General and administrative expense ratio	18.3		%	31.9		%	9.3		%	16.9		%
Expense ratio	28.5		%	52.4		%	29.0		%	31.7		%
Combined ratio	96.0		%	108.9		%	85.4		%	94.0		%

Six Months Ended June 30, 2014	North American  Insurance			Global Markets Insurance			Reinsurance			Total
Gross premiums written	$	818,252		$	131,961		$	711,585		$	1,661,798
Net premiums written	540,540			81,780			703,218			1,325,538
Net premiums earned	531,251			73,009			463,272			1,067,532
Net losses and loss expenses	(339,904		)	(7,062		)	(243,175		)	(590,141		)
Acquisition costs	(49,504		)	(7,302		)	(85,195		)	(142,001		)
General and administrative expenses	(106,142		)	(32,059		)	(38,327		)	(176,528		)
Underwriting income	35,701			26,586			96,575			158,862
Other insurance-related income	—			—			—			—
Other insurance-related expenses	—			—			—			—
Segment income	35,701			26,586			96,575			158,862
Net investment income										84,412
Net realized investment gains										139,422
Amortization of intangible assets										(1,267		)
Interest expense										(29,126		)
Foreign exchange loss										(700		)
Income before income taxes										$	351,603
Loss and loss expense ratio	64.0		%	9.7		%	52.5		%	55.3		%
Acquisition cost ratio	9.3		%	10.0		%	18.4		%	13.3		%
General and administrative expense ratio	20.0		%	43.9		%	8.3		%	16.5		%
Expense ratio	29.3		%	53.9		%	26.7		%	29.8		%
Combined ratio	93.3		%	63.6		%	79.2		%	85.1		%

Analysis of gross written premium by geographic location

The following table shows an analysis of the Company’s gross premiums written by geographic location of the Company’s subsidiaries and branches. All intercompany premiums have been eliminated.

	Three Months Ended   June 30,				Six Months Ended   June 30,
	2015		2014		2015		2014
United States	$	483,115	$	442,549	$	1,019,747	$	963,321
Bermuda	167,874		185,872		364,502		415,503
Asia Pacific	93,226		50,905		133,283		97,729
Europe	76,260		77,985		180,230		181,321
Canada	5,495		3,094		8,822		3,924
Total gross premiums written	$	825,970	$	760,405	$	1,706,584	$	1,661,798

Net premiums earned by segment and line of business

The following table shows the Company's net premiums earned by line of business for each segment for each of the periods indicated.

	Three Months Ended   June 30,				Six Months Ended   June 30,
	2015		2014		2015		2014
North American Insurance:
General casualty	$	109,218	$	78,565	$	214,143	$	154,865
Professional liability	84,411		64,259		163,327		128,531
Healthcare	38,396		43,323		76,437		85,817
Programs	36,710		28,708		70,857		65,478
General property	27,140		30,539		55,140		59,176
Inland marine	15,380		10,577		28,728		19,468
Environmental	7,273		4,774		14,095		9,360
Other	10,013		5,055		18,784		8,556
Total	328,541		265,800		641,511		531,251
Global Markets Insurance:
Professional liability	22,347		12,918		41,850		24,638
General casualty	21,714		3,208		27,626		5,901
General property	18,297		8,759		26,529		16,998
Motor	9,319		—		9,319		—
Marine	8,680		710		10,931		918
Aviation	5,351		4,733		11,304		10,370
Construction	4,955		—		5,261		—
Trade credit	3,986		4,720		8,261		8,732
Healthcare	3,800		2,950		7,406		5,452
Other	4,177		—		4,179		—
Total	102,626		37,998		152,666		73,009
Reinsurance:
Property	104,817		128,931		209,168		266,014
Casualty	58,880		50,161		115,782		97,677
Specialty	51,512		54,357		95,797		99,581
Total	215,209		233,449		420,747		463,272
Total net premiums earned	$	646,376	$	537,247	$	1,214,924	$	1,067,532