Financial Guarantee Insurance Contracts Earned Premiums by Geographic Location (Details) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Premiums Earned, Net, Financial Guarantee Insurance Contracts	$ 52,989	$ 53,218	$ 143,754	$ 147,420
United States [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	31,929	45,257	108,556	126,003
United Kingdom [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	17,273	6,018	28,094	19,111
Other International [Member] \| Reportable Geographical Components [Member]
Premiums Earned, Net, Financial Guarantee Insurance Contracts	$ 3,787	$ 1,943	$ 7,104	$ 2,306

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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