Consolidated Statements of Cash Flows (USD $) In Thousands	3 Months Ended
Mar. 31, 2011	Mar. 31, 2010
Net cash flows provided by (used in) operating activities	$ (122,143)	$ (210,399)
Fixed maturity securities:
Purchases	(511,679)	(418,032)
Sales	299,877	187,800
Maturities	183,587	265,268
Net sales (purchases) of short-term investments	242,296	219,827
Net proceeds from paydowns on financial guaranty variable interest entities' assets	162,500	60,687
Other	4,246	4,867
Net cash flows provided by (used in) investing activities	380,827	320,417
Financing activities
Dividends paid	(8,286)	(8,305)
Share activity under option and incentive plans	(2,312)	(2,583)
Net paydowns of financial guaranty variable interest entities' liabilities	(241,618)	(46,157)
Repayment of long-term debt	(5,095)	(6,363)
Net cash flows provided by (used in) financing activities	(257,311)	(63,408)
Effect of exchange rate changes	1,825	(254)
Increase (decrease) in cash	3,198	46,356
Cash at beginning of period	108,389	44,133
Cash at end of period	111,587	90,489
Cash paid (received) during the period for:
Income taxes	51,465	136,645
Interest	$ 12,190	$ 12,588

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The net change between the beginning and ending balance of cash.

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Payments to reduce the outstanding balance of consolidated variable interest entities recourse and non-recourse liabilities. The Company consolidated these variable interest entities as the result of its control rights obtained under financial guaranty insurance contracts.

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Proceeds received on consolidated variable interest entities assets. The Company consolidates these variable interest entities as the result of its control rights obtained under financial guaranty insurance contracts.

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This element represents cash inflow (outflow) in satisfaction of withholding tax requirements in enterprise's financing activities, option exercises and other share activity under incentive plans.

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Unrestricted cash available for day-to-day operating needs.

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The effect of exchange rate changes on cash balances held in foreign currencies.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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The amount of cash paid during the current period for interest owed on money borrowed, net of interest capitalized.

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The net cash inflow (outflow) from financing activity for the period.

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The net cash inflow (outflow) from investing activity.

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The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities generally involve producing and delivering goods and providing services. Operating activity cash flows include transactions, adjustments, and changes in value that are not defined as investing or financing activities.

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The net cash outflow (inflow) from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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The cash outflow from the distribution of an entity's earnings in the form of dividends to common shareholders.

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The cash outflow to acquire debt securities classified as available-for-sale securities, because they are not classified as either held-to-maturity securities or trading securities.

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The cash inflow associated maturities (principal being due), prepayments and calls (requests of early payments) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

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The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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The cash outflow for a borrowing supported by a written promise to pay an obligation.

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