Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities
Net earnings	$ 154,653	$ 125,420
Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:
Depreciation and amortization	34,905	42,083
Net realized capital (gains) losses	(35,893)	(43,151)
Other than temporary impairment losses	20,759	52,281
(Increase) decrease in reinsurance recoverables, net of reinsurance payable	65,627	215
(Increase) decrease in premium balances receivable	(3,708)	44,282
(Increase) decrease in ceded unearned premiums	2	(12,756)
(Increase) decrease in deferred acquisition costs	(30,197)	(16,662)
Increase (decrease) in unearned premiums	93,998	68,644
Increase (decrease) in loss and loss adjustment expenses	(40,512)	(182,881)
Change in unrealized foreign exchange losses (gains)	45,552	154,741
Other, net	(265,606)	(14,895)
Net adjustments	(115,073)	91,901
Net cash provided by (used in) operating activities	39,580	217,321
Cash flows from investing activities
Purchases of debt securities	(1,844,101)	(2,122,464)
Purchases of equity securities	(551,815)	(1,385,109)
Sales of debt securities	1,800,873	1,596,406
Maturities and redemptions of debt securities	237,162	353,149
Sales of equity securities	665,994	1,132,816
Net (purchase) sale in short-term investments	(142,622)	230,725
Purchases of property and equipment	(2,088)	(10,609)
Purchase of subsidiary, net of cash acquired	(1,020)	(43,900)
Other, net	(122,288)	1,232
Net cash provided by (used in) investing activities	40,095	(247,754)
Cash flows from financing activities
Treasury stock acquisitions	(53,288)	(26,632)
Other, net	5,734	7,344
Net cash provided by (used in) financing activities	(47,554)	(19,288)
Effect of exchange rate changes on cash	2,355	(18,053)
Net increase (decrease) in cash	34,476	(67,774)
Cash at beginning of period	475,267	605,259
Cash at end of period	509,743	537,485
Cash paid during period for:
Interest paid	16,115	16,406
Income taxes paid (refund received)	$ 11,737	$ (1,787)