CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues
Net premiums earned	$ 1,156,941	$ 1,104,003	$ 2,260,663	$ 2,192,628
Net investment income	104,672	45,040	218,836	138,140
Other insurance related income (loss)	5,817	1,996	8,598	(6,710)
Net investment gains (losses):
Allowance for expected credit losses	150	13,761	239	(6,257)
Impairment losses	0	(112)	0	(1,302)
Other realized and unrealized investment gains (losses)	73,143	39,394	102,697	(2,272)
Total net investment gains (losses)	73,293	53,043	102,936	(9,831)
Total revenues	1,340,723	1,204,082	2,591,033	2,314,227
Expenses
Net losses and loss expenses	666,473	676,261	1,381,190	1,584,335
Acquisition costs	219,070	228,502	437,941	467,152
General and administrative expenses	162,452	140,652	320,860	297,712
Foreign exchange losses (gains)	19,602	9,709	23,716	(51,974)
Interest expense and financing costs	15,235	20,595	30,806	44,067
Reorganization expenses	0	392	0	(591)
Amortization of value of business acquired	1,028	1,285	2,056	3,083
Amortization of intangible assets	3,324	2,855	6,013	5,725
Total expenses	1,087,184	1,080,251	2,202,582	2,349,509
Income (loss) before income taxes and interest in income (loss) of equity method investments	253,539	123,831	388,451	(35,282)
Income tax expense	(27,865)	(10,893)	(48,641)	(6,026)
Interest in income (loss) of equity method investments	9,799	7,102	18,960	(16,475)
Net income (loss)	235,473	120,040	358,770	(57,783)
Preferred share dividends	7,563	7,563	15,125	15,125
Net income (loss) available (attributable) to common shareholders	$ 227,910	$ 112,477	$ 343,645	$ (72,908)
Earnings (loss) per common share:
Earnings (loss) per common share (in usd per share)	$ 2.69	$ 1.33	$ 4.06	$ (0.87)
Earnings (loss) per diluted common share (in usd per share)	$ 2.67	$ 1.33	$ 4.04	$ (0.87)
Weighted average common shares outstanding (in shares)	84,764	84,303	84,640	84,198
Weighted average diluted common shares outstanding (in shares)	85,267	84,600	85,117	84,198