Schedule IV - Reinsurance (Detail) - Successor [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Direct Premiums Written	$ (14,313)	$ (53,837)	$ (37,572)
Ceded Premiums Written	(2,104)	(8,772)	(3,001)
Assumed Premiums Written	0	0	0
Premiums Written, Net	$ (12,209)	$ (45,065)	$ (34,571)
Percentage of Amount Assumed to Net	0.00%	0.00%	0.00%

Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net

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- Definition

Amount of written premiums assumed from other entities.

+ References

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- Definition

Amount of written premiums ceded to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written.

+ References

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 605
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

+ References

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 605
-Section 50
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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