Unaudited Quarterly Financial Data

12 Months Ended

Dec. 31, 2017

Quarterly Financial Information Disclosure [Abstract]

Unaudited quarterly financial data

Unaudited Quarterly Financial Data

The following is a summary of the unaudited quarterly financial data for 2017 and 2016:

(U.S. dollars in thousands, except per share amounts)	First Quarter		Second Quarter		Third Quarter			Fourth Quarter
2017
Net premiums earned	$	2,522,791	$	2,516,917	$	2,620,902		$	2,676,002
Underwriting profit (loss)	$	138,456	$	188,261	$	(1,235,734	)	$	14,193
Net income (loss) attributable to common shareholders	$	152,843	$	301,620	$	(1,043,689	)	$	28,828
Net income (loss) per common share and common equivalent – basic	$	0.58	$	1.16	$	(4.06	)	$	0.11
Net income (loss) per common share and common equivalent – diluted	$	0.57	$	1.14	$	(4.06	)	$	0.11
2016
Net premiums earned	$	2,354,610	$	2,532,212	$	2,434,037		$	2,457,075
Underwriting profit (loss)	$	172,037	$	97,691	$	162,192		$	115,405
Net income (loss) attributable to common shareholders	$	21,885	$	43,782	$	70,601		$	304,700
Net income (loss) per common share and common equivalent – basic	$	0.07	$	0.16	$	0.26		$	1.13
Net income (loss) per common share and common equivalent – diluted	$	0.07	$	0.15	$	0.25		$	1.12