CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues
Net premiums earned	$ 3,707,065	$ 3,415,463	$ 3,314,961
Net investment income	409,312	380,957	362,430
Other insurance related income	4,424	2,676	2,396
Net realized investment gains:
Other-than-temporary impairment (OTTI) losses	(9,362)	(24,234)	(16,446)
Non-credit portion of OTTI losses recognized in other comprehensive income	0	0	585
Other net realized investment gains	84,926	151,703	137,300
Total net realized investment gains	75,564	127,469	121,439
Total revenues	4,196,365	3,926,565	3,801,226
Expenses
Net losses and loss expenses	2,134,195	2,096,028	2,675,052
Acquisition costs	664,191	627,653	587,469
General and administrative expenses	575,390	560,981	459,151
Foreign exchange losses (gains)	26,143	29,512	(44,582)
Interest expense and financing costs	61,979	61,863	62,598
Total expenses	3,461,898	3,376,037	3,739,688
Income before income taxes	734,467	550,528	61,538
Income tax expense	7,002	3,287	15,233
Net income	727,465	547,241	46,305
Preferred share dividends	40,474	38,228	36,875
Loss on repurchase of preferred shares	3,081	14,009	0
Net income available to common shareholders	$ 683,910	$ 495,004	$ 9,430
Net income per common share:
Basic net income	$ 6.02	$ 4.05	$ 0.08
Diluted net income	$ 5.93	$ 4.00	$ 0.07
Weighted average number of common shares outstanding - basic	113,636	122,148	122,499
Weighted average number of common shares outstanding - diluted	115,328	123,654	128,122