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Related Party Transactions - Additional Information (Detail) - Fox Paine and Company - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Company's total outstanding voting power	82.00%
Minimum voting power required to nominate Directors	25.00%
Management fees	$ 500	$ 500
Unpaid management fees	7,300		$ 6,800
Advisory services fees estimated	$ 12,500
Estimated percentage of services provided	50.00%
Other Liabilities
Related Party Transaction [Line Items]
Advisory services fees estimated	$ 6,250
Corporate Expense and Other Accrued Liabilities
Related Party Transaction [Line Items]
Advisory services fees estimated	$ 6,250

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- Definition

Percentage of investee's stock owned by parent

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Estimated percentage of investment advisory services provided during period.

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- Definition

Management Fee Payable Related Parties

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Management Fees Related Parties

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Minimum Voting Power To Nominate Directors

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X

- Definition

Amount of fees earned from providing investment advice and research to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(a),(d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

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.

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