Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net cash flows provided by (used in) operating activities	$ 75,256	$ (122,143)
Fixed maturity securities:
Purchases	(382,588)	(511,679)
Sales	189,346	299,877
Maturities	253,488	183,587
Net sales (purchases) of short-term investments	(142,735)	242,296
Net proceeds from paydowns on financial guaranty variable interest entities' assets	137,595	162,500
Other	51,607	4,246
Net cash flows provided by (used in) investing activities	106,713	380,827
Financing activities
Dividends paid	(16,425)	(8,286)
Share activity under option and incentive plans	(2,478)	(2,312)
Net paydowns of financial guaranty variable interest entities' liabilities	(192,882)	(241,618)
Repayment of long-term debt	(5,461)	(5,095)
Net cash flows provided by (used in) financing activities	(217,246)	(257,311)
Effect of exchange rate changes	2,736	1,825
Increase (decrease) in cash	(32,541)	3,198
Cash at beginning of period	214,544	108,389
Cash at end of period	182,003	111,587
Cash paid (received) during the period for:
Income taxes	2,000	51,465
Interest	$ 12,082	$ 12,190