Financial Guarantee Insurance Contracts Earned Premiums by Geographic Location (Details) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Premiums Earned, Net, Financial Guarantee Insurance Contracts	$ 25,836	$ 43,152	$ 56,719	$ 90,765
United States [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	19,752	36,006	44,469	76,627
United Kingdom [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	4,958	5,558	9,815	10,821
Other International [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	$ 1,126	$ 1,588	$ 2,435	$ 3,317

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6811-158387

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=84167274&loc=d3e27175-158546

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.1)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6816-158387

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6933001&loc=SL5747862-161289

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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