CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ 618,609	$ (120,424)	$ 323,473
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Net investment gains	(134,279)	(129,133)	(91,233)
Net realized and unrealized gains on other investments	(180,329)	(16,059)	(60,038)
Amortization of fixed maturities	35,839	32,893	18,499
Interest in (income) loss of equity method investments	(32,084)	3,612	(9,718)
Amortization of value of business acquired	3,854	5,139	26,722
Other amortization and depreciation	66,977	65,797	75,229
Share-based compensation expense, net of cash payments	37,744	29,005	32,491
Non-cash foreign exchange gains	0	0	(6,043)
Changes in:
Accrued interest receivable	633	13,097	2,140
Reinsurance recoverable on unpaid losses and loss expenses	(527,362)	(618,040)	(359,543)
Reinsurance recoverable on paid losses and loss expenses	(207,429)	(105,820)	(52,533)
Deferred acquisition costs	(34,386)	60,828	74,331
Prepaid reinsurance premiums	(185,646)	(94,122)	(88,789)
Reserve for losses and loss expenses	737,342	1,178,292	467,428
Unearned premiums	409,858	62,999	(7,958)
Insurance and reinsurance balances, net	349,502	72,503	(51,075)
Other items	155,979	(97,064)	(94,379)
Net cash provided by operating activities	1,114,822	343,503	199,004
Purchases of:
Fixed maturities, available for sale	(12,133,755)	(10,494,198)	(9,994,025)
Fixed maturities, held to maturity	(196,775)	0	0
Equity securities	(137,247)	(117,883)	(58,022)
Mortgage loans	(145,832)	(199,259)	(194,020)
Other investments	(263,712)	(166,602)	(218,178)
Short-term investments	(159,056)	(365,170)	(179,230)
Proceeds from the sale of:
Fixed maturities, available for sale	9,203,241	9,784,137	8,018,658
Equity securities	24,862	119,381	36,016
Other investments	324,810	166,976	249,129
Short-term investments	177,672	171,976	266,057
Proceeds from redemption of fixed maturities, available for sale	1,817,482	1,526,396	1,282,796
Proceeds from redemption of fixed maturities, held to maturity	155,809	0	0
Proceeds from redemption of short-term investments	111,417	69,707	19,366
Proceeds from the repayment of mortgage loans	145,621	39,121	60,244
Purchase of other assets	(38,732)	(44,661)	(63,106)
Net cash provided by (used in) investing activities	(1,114,195)	489,921	(774,315)
Cash flows from financing activities:
Net proceeds from issuance of senior notes	0	0	717,509
Redemption of senior notes	0	(500,000)	(250,000)
Repurchase of preferred shares	0	(225,000)	0
Taxes paid on withholding shares	(10,242)	(10,382)	(10,165)
Dividends paid - common shares	(145,603)	(141,590)	(137,209)
Dividends paid - preferred shares	(30,250)	(31,831)	(42,625)
Net cash provided by (used in) financing activities	(186,095)	(908,803)	277,510
Effect of exchange rate changes on foreign currency cash, cash equivalents and restricted cash	(74)	2,154	44,238
Decrease in cash, cash equivalents and restricted cash	(185,542)	(73,225)	(253,563)
Cash, cash equivalents and restricted cash - beginning of year	1,503,232	1,576,457	1,830,020
Cash, cash equivalents and restricted cash - end of year	1,317,690	1,503,232	1,576,457
Supplemental disclosures of cash flow information:
Income taxes paid	45,083	4,414	39,949
Interest paid	$ 59,400	$ 54,108	$ 59,563