Fair Value and Future Funding Commitments Related to These Investments (Detail) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		$ 97,018	$ 47,279
Future Funding Commitments		31,214	31,720
European Non-Performing Loan Fund, LP | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	[1]	10,808	13,530
Future Funding Commitments	[1]	14,214	14,214
Distressed Debt Fund, LP | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	[2]	15,721	23,966
Future Funding Commitments	[2]	17,000	17,000
Mortgage Debt Fund, LP | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	[3]	10,489	9,783
Future Funding Commitments	[3]	0	506
Credit Fund, LLC | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	[4]	60,000	0
Future Funding Commitments	[4]	$ 0	$ 0

[1] This limited partnership invests in distressed securities and assets through senior and subordinated, secured and unsecured debt and equity, in both public and private large-cap and middle-market companies.  The Company does not have the ability to sell or transfer its limited partnership interest without consent from the general partner.  The Company does not have the contractual option to redeem its limited partnership interest but receives distributions based on the liquidation of the underlying assets.  

[2] This limited partnership invests in stressed and distressed securities and structured products.  The Company does not have the ability to sell or transfer its limited partnership interest without consent from the general partner.  The Company does not have the contractual option to redeem its limited partnership interest but receives distributions based on the liquidation of the underlying assets.

[3] This limited partnership invests in REIT qualifying assets such as mortgage loans, investor property loans, and commercial mortgage loans.  The Company does not have the ability to sell or transfer its limited partnership interest without consent from the general partner.  The Company does not have the contractual option to redeem its limited partnership interest but receives distributions based on the liquidation of the underlying assets.

[4] This limited liability company invests in a broad portfolio of non-investment grade loans, secured and unsecured corporate debt, credit default swaps, reverse repurchase agreements and synthetic indices.  The Company does have the ability to sell its interest by providing notice to the fund.