Financial Guarantee Insurance Contracts Earned Premiums by Geographic Location (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Premiums Earned, Net, Financial Guarantee Insurance Contracts	$ 10,466	$ 25,640	$ 46,057	$ 82,359
United States [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	10,588	19,539	44,457	64,009
United Kingdom [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	4,354	4,523	12,769	14,337
Other International [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	$ (4,476)	$ 1,578	$ (11,169)	$ 4,013

Amount, after premiums ceded to other entities and premiums assumed by the entity, of financial guarantee premiums earned.

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