Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
CASH FROM OPERATING ACTIVITIES:
Net income to common stockholders	$ 562,638	$ 508,392
Adjustments to reconcile net income to net cash from (used in) operating activities:
Net realized and unrealized gains on investments	(143,691)	(140,429)
Depreciation and amortization	42,007	76,541
Noncontrolling interests	1,554	4,402
Investment funds	(77,284)	(94,075)
Stock incentive plans	38,440	28,528
Change in:
Arbitrage trading account	(20,422)	(14,795)
Premiums and fees receivable	(206,867)	(107,347)
Reinsurance accounts	(116,359)	(114,298)
Deferred policy acquisition costs	(30,537)	(7,466)
Income taxes	(16,449)	(99,945)
Reserves for losses and loss expenses	443,454	230,112
Unearned premiums	336,664	176,736
Other	(18,104)	(103,832)
Net cash from operating activities	795,044	342,524
CASH USED IN INVESTING ACTIVITIES:
Proceeds from sale of fixed maturity securities	1,341,688	2,841,642
Proceeds from sale of equity securities	40,709	449,388
Distributions from (contributions to) investment funds	187,321	(3,505)
Proceeds from maturities and prepayments of fixed maturity securities	2,278,264	1,957,724
Purchase of fixed maturity securities	(3,853,108)	(5,187,501)
Purchase of equity securities	(66,305)	(87,059)
Real estate purchased	(176,538)	(454,410)
Change in loans receivable	3,156	(14,345)
Net additions to property, furniture and equipment	(1,802)	(35,582)
Change in balances due to security brokers	54,620	5,601
Cash received in connection with business disposition	0	8,664
Payment for business purchased net of cash acquired	0	(6,637)
Other	45	(443)
Net cash used in investing activities	(191,950)	(526,463)
CASH (USED IN) FROM FINANCING ACTIVITIES:
Repayment of senior notes and other debt	(448,409)	(23)
Net proceeds from issuance of debt	0	198,905
Cash dividends to common stockholders	(130,035)	(96,131)
Purchase of common treasury shares	0	(6,799)
Other, net	(20,750)	(4,238)
Net cash (used in) from financing activities	(599,194)	91,714
Net impact on cash due to change in foreign exchange rates	(8,952)	(38,880)
Net change in cash and cash equivalents	(5,052)	(131,105)
Cash and cash equivalents at beginning of year	817,602	950,471
Cash and cash equivalents at end of period	$ 812,550	$ 819,366