Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
CASH FROM (USED IN) OPERATING ACTIVITIES:
Net income to common stockholders	$ 135,318	$ 115,590
Adjustments to reconcile net income to net cash from operating activities:
Net investment gains	(47,491)	(29,284)
Depreciation and amortization	22,212	22,079
Noncontrolling interests	(86)	5
Investment funds	(27,624)	(15,812)
Stock incentive plans	7,447	6,468
Change in:
Arbitrage trading account	(2,946)	(6,532)
Premiums and fees receivable	(97,077)	(88,106)
Reinsurance accounts	(16,857)	(142,848)
Deferred policy acquisition costs	(11,483)	(21,333)
Deferred income taxes	(13,600)	(9)
Reserves for losses and loss expenses	47,443	143,704
Unearned premiums	115,434	152,731
Other liabilities	(36,928)	(81,210)
Net cash from (used in) operating activities	73,762	55,443
CASH FROM (USED IN) INVESTING ACTIVITIES:
Proceeds from sale of fixed matuirty securities	295,134	395,115
Proceeds from sale of equity securities	32,575	63,232
Distributions from (contributions to) investment funds	24,744	(79,410)
Proceeds from maturities and prepayments of fixed maturity securities	408,647	407,780
Purchase of fixed maturity securities	(872,588)	(835,804)
Purchase of equity securities	(68,652)	(24,694)
Real estate purchased	(5,611)	(58,098)
Change in loans receivable	(93,934)	4,809
Net additions to real estate, furniture and equipment	(15,055)	(11,884)
Change in balances due to security brokers	16,146	74,986
Payment for business purchased, net of cash acquired	0	(11,060)
Net cash from (used in) investing activities	(278,594)	(75,028)
CASH FROM (USED IN) FINANCING ACTIVITIES:
Net proceeds from issuance of debt	354,315	0
Net proceeds from stock options exercised	3,428	13,217
Repayment of debt	(1,684)	(3,672)
Cash dividends to common stockholders	0	(9,911)
Purchase of common treasury shares	0	(23,303)
Other, net	10,446	15,703
Net cash from (used in) financing activities	366,505	(7,966)
Net impact on cash due to change in foreign exchange rates	8,992	14,750
Net change in cash and cash equivalents	170,665	(12,801)
Cash and cash equivalents at beginning of year	911,742	642,952
Cash and cash equivalents at end of period	$ 1,082,407	$ 630,151

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).