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Amount of additional Debt Securities that can be issued

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Economic Income Ratio Following Third Anniversary of Closing Date

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Economic Income Ratio Through Third Anniversary of Closing Date

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Fee-paying assets under management for two successive quarters

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Maximum annual amortization payments

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Percent discount on repayment within nine months of repayment of 2019 Preferred Units

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Percent of original principal amount amortized in quarterly installments

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Restricted payment basket for preferred dividends

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of assets pledged to secure a debt instrument.

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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.

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

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Debt Obligations - Additional Information (Detail) - USD ($) $ in Thousands			12 Months Ended
	Feb. 13, 2020	Feb. 07, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 10, 2018
Debt Instrument [Line Items]
Amount of 2016 Preferred Units Restructured as Debt Securities		$ 200,000
Borrowings outstanding			$ 305,966
Repayment of debt obligations			192,790	$ 595,463	$ 167,516
Debt Securities
Debt Instrument [Line Items]
Amount of 2016 Preferred Units Restructured as Debt Securities			$ 200,000
Maturity date			Apr. 01, 2026
Percent of original principal amount amortized in quarterly installments			5.00%
Maximum annual amortization payments			$ 40,000
Percent discount on repayment within nine months of repayment of 2019 Preferred Units			5.00%
Borrowings outstanding			$ 200,000
2018 Term Loan
Debt Instrument [Line Items]
Maturity date			Apr. 10, 2023
Borrowings outstanding			$ 45,000			$ 250,000
Repayment of debt obligations		$ 100,000	55,000
Fee-paying assets under management covenant amount			$ 20,000,000
Economic income ratio through third anniversary of closing date			300.00%
Economic income ratio following third anniversary of closing date			250.00%
Amount of additional Debt Securities that can be issued			$ 200,000
Restricted payment basket for preferred dividends			$ 12,000
2018 Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit facility borrowing capacity						$ 100,000
2018 Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Undrawn commitment fee			0.20%
2018 Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Undrawn commitment fee			0.75%
CLO Investments Loans
Debt Instrument [Line Items]
Borrowings outstanding			$ 60,966
Collateral on CLO Investments Loans			$ 65,900	$ 112,800
LIBOR \| Debt Securities
Debt Instrument [Line Items]
Interest rate spread over basis			4.75%
LIBOR \| 2018 Term Loan
Debt Instrument [Line Items]
Interest rate spread over basis			4.75%
Base Rate \| Debt Securities
Debt Instrument [Line Items]
Interest rate spread over basis			3.75%
Base Rate \| 2018 Term Loan
Debt Instrument [Line Items]
Interest rate spread over basis			3.75%
Subsequent Event \| 2018 Term Loan
Debt Instrument [Line Items]
Repayment of debt obligations	$ 27,000