Debt Obligations - Schedule of CLO Investments Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Borrowings outstanding	$ 286,728	$ 289,987
CLO Investments Loans
Debt Instrument [Line Items]
Borrowings outstanding	$ 60,625	95,807
CLO Investments Loans \| November 28, 2016
Debt Instrument [Line Items]
Maturity date	Dec. 15, 2023
Borrowings outstanding	$ 0	17,235
CLO Investments Loans \| November 28, 2016 \| EURIBOR
Debt Instrument [Line Items]
Interest rate spread over basis	2.23%
CLO Investments Loans \| June 07, 2017
Debt Instrument [Line Items]
Maturity date	Nov. 16, 2029
Borrowings outstanding	$ 17,245	17,224
CLO Investments Loans \| June 07, 2017 \| LIBOR
Debt Instrument [Line Items]
Interest rate spread over basis	1.48%
CLO Investments Loans \| August 02, 2017
Debt Instrument [Line Items]
Maturity date	Jan. 21, 2030
Borrowings outstanding	$ 21,679	21,674
CLO Investments Loans \| August 02, 2017 \| LIBOR
Debt Instrument [Line Items]
Interest rate spread over basis	1.41%
CLO Investments Loans \| September 14, 2017
Debt Instrument [Line Items]
Maturity date	Sep. 14, 2024
Borrowings outstanding	$ 18,237	18,614
CLO Investments Loans \| September 14, 2017 \| EURIBOR
Debt Instrument [Line Items]
Interest rate spread over basis	2.21%
CLO Investments Loans \| February 21, 2018
Debt Instrument [Line Items]
Maturity date	Feb. 21, 2019
Borrowings outstanding	$ 0	21,060
CLO Investments Loans \| February 21, 2018 \| LIBOR
Debt Instrument [Line Items]
Interest rate spread over basis	1.27%
CLO Investments Loans \| August 1, 2019
Debt Instrument [Line Items]
Maturity date	Jun. 29, 2021
Borrowings outstanding	$ 3,464	$ 0
CLO Investments Loans \| August 1, 2019 \| EURIBOR
Debt Instrument [Line Items]
Interest rate spread over basis	1.15%

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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.

+ References

No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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