Consolidated Statements of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Net cash flows provided by (used in) operating activities	$ 631,946	$ (217,674)
Fixed maturity securities:
Purchases	(1,349,745)	(1,166,379)
Sales	685,980	780,818
Maturities	325,750	488,552
Net sales (purchases) of short-term investments	(49,901)	248,780
Net proceeds from paydowns on financial guaranty variable interest entities' assets	423,977	217,329
Other	8,696	8,317
Net cash flows provided by (used in) investing activities	44,757	577,417
Financing activities
Dividends paid	(16,577)	(16,613)
Repurchases of common stock		(10,457)
Share activity under option and incentive plans	(2,652)	(2,233)
Net paydowns of financial guaranty variable interest entities' liabilities	(593,294)	(259,367)
Repayment of long-term debt	(10,294)	(10,850)
Net cash flows provided by (used in) financing activities	(622,817)	(299,520)
Effect of foreign exchange rate changes	3,215	(3,090)
Increase (decrease) in cash	57,101	57,133
Cash at beginning of period	108,389	44,133
Cash at end of period	165,490	101,266
Cash paid (received) during the period for:
Income taxes	89,202	136,645
Interest	$ 45,711	$ 46,261