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 unamortized debt discount (premium) and debt issuance costs.

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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.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Debt Obligations - Schedule of Debt Principal Payments (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Apr. 10, 2018
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 0
Long-term Debt, Maturities, Repayments of Principal in Year Two	3,464
Long-term Debt, Maturities, Repayments of Principal in Year Three	40,000
Long-term Debt, Maturities, Repayments of Principal in Year Four	85,000
Long-term Debt, Maturities, Repayments of Principal in Year Five	58,301
Long-term Debt, Maturities, Repayments of Principal after Year Five	119,201
Borrowings outstanding	305,966
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(19,238)
Debt obligations	286,728	$ 289,987
Debt Securities
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	0
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	40,000
Long-term Debt, Maturities, Repayments of Principal in Year Four	40,000
Long-term Debt, Maturities, Repayments of Principal in Year Five	40,000
Long-term Debt, Maturities, Repayments of Principal after Year Five	80,000
Borrowings outstanding	200,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(18,002)
Debt obligations	181,998
2018 Term Loan
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	0
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	0
Long-term Debt, Maturities, Repayments of Principal in Year Four	45,000
Long-term Debt, Maturities, Repayments of Principal in Year Five	0
Long-term Debt, Maturities, Repayments of Principal after Year Five	0
Borrowings outstanding	45,000		$ 250,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(895)
Debt obligations	44,105
CLO Investments Loans
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	0
Long-term Debt, Maturities, Repayments of Principal in Year Two	3,464
Long-term Debt, Maturities, Repayments of Principal in Year Three	0
Long-term Debt, Maturities, Repayments of Principal in Year Four	0
Long-term Debt, Maturities, Repayments of Principal in Year Five	18,301
Long-term Debt, Maturities, Repayments of Principal after Year Five	39,201
Borrowings outstanding	60,966
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(341)
Debt obligations	$ 60,625	$ 95,807