Class D Shares Institutional Class Nature of the Fund [Member] Master-Feeder Structure [Member] Multiple Levels of Expense [Member] Operating Deficits [Member] Limitations on Transfer [Member] Repurchase Risks [Member] Nasdaq Secondary Fund Auction Risk [Member] Availability of Suitable Investments [Member] Economic Environment [Member] Diverse Shareholders [Member] General Economic and Market Risk [Member] Illiquidity of Investments [Member] Investments in Non-Voting Stock; Inability to Vote [Member] Difficulty of Valuing the Master Fund’s Investments [Member] Inability to Meet Investment Objective or Investment Strategy [Member] Performance of Investments [Member] Leverage [Member] Non-Diversification Risk [Member] Control of Portfolio Companies [Member] Reliance on Management [Member] Possibility of Fraud and Other Misconduct [Member] Foreign Investments [Member] Secondary Investments [Member] Timing of Investment Risk [Member] Distressed, Special Situations and Venture Investments [Member] Emerging Markets [Member] Market Disruption Risk and Terrorism Risk [Member] Natural Disaster/Epidemic Risk [Member] Investment and Repatriation Restrictions [Member] Competition [Member] Cybersecurity Risk [Member] Lack of Regulatory Oversight [Member] Legal, Tax and Regulatory Risks [Member] Enhanced Scrutiny and Potential Regulation of the Private Investment Partnership Industry and the Financial Services Industry [Member] Investment Banking and Other Fees [Member] Material, Non-Public Information [Member] Constraints of Confidentiality Agreements [Member] Provision of Managerial Assistance [Member] Disposition of Investments [Member] Failure to Make Capital Contributions [Member] Indemnification [Member] Tax Risks [Member] Key Personnel [Member] Risks Related to Electronic Communication [Member] Potential Conflicts of Interest [Member] Debt Investments Generally [Member] Default, Recovery and Restructuring Risks [Member] Highly Leveraged Companies [Member] Secondary Market Investments [Member] Risks of Equity Items [Member] Covenant-Light Loans [Member] Rising Interest Rate Risks [Member] Nature of Bankruptcy Proceedings [Member] Insolvency Considerations [Member] Priority of Liens arising by Operation of Law [Member] Structured Notes [Member] Loan Investments [Member] Collateralized Obligations Generally [Member] ABS and MBS Generally [Member] Risks Related to Balloon Loans [Member] Risk of Decline in Particular Industries or Businesses [Member] Construction, Redevelopment and Renovation Risks [Member] Risk of Eminent Domain [Member] Risks Associated with Investments in REITs [Member] Environmental Liabilities [Member] Non-U.S. Borrowers [Member] Real Estate-Related Investments [Member] Development [Member] Office Properties [Member] Multifamily Properties [Member] Retail Properties [Member] Student Housing [Member] Assisted-Living and Seniors’ Housing [Member] Risks Associated with Commercial Mortgage Loans [Member] Risks Associated with Residential Mortgage Loans [Member] Risk of Decline in Value of Real Estate Collateral [Member] Litigation at the Property Level [Member] Commodity Prices [Member] Sub-Sector Specific Risk [Member] Supply Risk [Member] Demand for Oil and Gas [Member] Inherent Operating Risks [Member] Drilling, Engineering, Construction and Development Risks [Member] Evaluation Limitations [Member] Royalty Interest Risks [Member] Legislation and Regulatory Initiatives Relating to Hydraulic Fracturing [Member] Technology Innovation [Member] Unavailability of Equipment or Personnel [Member] Risk Factors Related to Midstream and Natural Gas Storage Industry [Member] Terrorist Activities Effect on Oil and Gas Prices [Member] Taxation of Oil and Gas Properties [Member] Construction and Right-of-Way Risk [Member] Renewable Energy [Member] Key Inputs [Member] Independent Contractors [Member] New Technologies and Products [Member] Power Purchase Agreement Risk [Member] Operating Pursuant to Complex Government Licenses, Leases, Concessions or Contracts [Member] Sovereign Risk [Member] Reliance on Power Transmission and Facilities [Member] Land Title Risks [Member] Climate Change Laws [Member] Regulatory Matters [Member] Infrastructure Risk Generally [Member] Environmental Matters [Member] Investments in Leveraged Infrastructure Assets [Member] Construction Risks [Member] Operating and Technical Risk [Member] Documentation Risks [Member] Regulatory Risks [Member] Cyclicality Risk [Member] Timberlands Business Competition [Member] Cyclical Nature of Timberlands Values [Member] Volatility of Forest Product Prices [Member] Long-term Supply Contracts [Member] Fire, Pest and Weather Damage to Properties [Member] Fast-growing Timberlands [Member] Subordinated Investments [Member] Fluctuations in Interest Rates [Member] Breach of Financing Agreement Covenants [Member] Adequacy of Insurance [Member] Uninsured Losses [Member] Alternative Investment Vehicles [Member] General Risks of Structured Finance Investments [Member]