CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues
Net premiums earned	$ 1,123,607	$ 1,185,548	$ 2,257,819	$ 2,352,950
Net investment income	137,949	109,960	245,254	210,961
Other insurance related income	2,925	3,730	9,852	10,335
Net investment gains (losses):
Other-than-temporary impairment (OTTI) losses	(834)	(1,674)	(4,870)	(2,088)
Other realized and unrealized investment gains (losses)	22,059	(43,419)	38,866	(57,835)
Total net investment gains (losses)	21,225	(45,093)	33,996	(59,923)
Total revenues	1,285,706	1,254,145	2,546,921	2,514,323
Expenses
Net losses and loss expenses	672,463	706,641	1,336,491	1,367,986
Acquisition costs	242,363	231,952	502,781	461,212
General and administrative expenses	165,395	165,213	340,486	335,049
Foreign exchange gains	(12,381)	(44,099)	(5,325)	(6,239)
Interest expense and financing costs	15,607	17,098	31,502	33,861
Transaction and reorganization expenses	3,276	18,772	18,096	31,825
Amortization of value of business acquired	7,194	53,407	20,298	110,517
Amortization of intangible assets	2,912	4,029	5,914	6,811
Total expenses	1,096,829	1,153,013	2,250,243	2,341,022
Income before income taxes and interest in income of equity method investments	188,877	101,132	296,678	173,301
Income tax (expense) benefit	(14,469)	(996)	(15,703)	40
Interest in income of equity method investments	2,635	3,378	4,853	3,378
Net income	177,043	103,514	285,828	176,719
Preferred share dividends	10,656	10,656	21,313	21,313
Net income available to common shareholders	$ 166,387	$ 92,858	$ 264,515	$ 155,406
Earnings per common share:
Earnings per common share (in usd per share)	$ 1.98	$ 1.11	$ 3.16	$ 1.86
Earnings per diluted common share (in usd per share)	$ 1.97	$ 1.11	$ 3.14	$ 1.85
Weighted average number of common shares outstanding - basic (in shares)	83,941	83,539	83,834	83,431
Weighted average number of common shares outstanding - diluted (in shares)	84,401	83,984	84,338	83,853