v3.26.1
Shareholder Report, Holdings (Details)
Jun. 30, 2026
Core Bond Series (Class I) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class I) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class I) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class I) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class I) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.70%
Core Bond Series (Class I) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class I) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class I) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Core Bond Series (Class I) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Core Bond Series (Class I) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class I) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Core Bond Series (Class I) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.00%
Core Bond Series (Class I) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Core Bond Series (Class I) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class I) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Core Bond Series (Class I) | U.S. Treasury Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.00%
Core Bond Series (Class I) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.40%
Core Bond Series (Class I) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.80%
Core Bond Series (Class I) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Core Bond Series (Class I) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Core Bond Series (Class S) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class S) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class S) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class S) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class S) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.70%
Core Bond Series (Class S) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class S) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class S) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Core Bond Series (Class S) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Core Bond Series (Class S) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class S) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Core Bond Series (Class S) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.00%
Core Bond Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Core Bond Series (Class S) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class S) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Core Bond Series (Class S) | U.S. Treasury Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.00%
Core Bond Series (Class S) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.40%
Core Bond Series (Class S) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.80%
Core Bond Series (Class S) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Core Bond Series (Class S) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Core Bond Series (Class W) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class W) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class W) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class W) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class W) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.70%
Core Bond Series (Class W) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class W) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class W) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Core Bond Series (Class W) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Core Bond Series (Class W) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class W) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Core Bond Series (Class W) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.00%
Core Bond Series (Class W) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Core Bond Series (Class W) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class W) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Core Bond Series (Class W) | U.S. Treasury Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.00%
Core Bond Series (Class W) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.40%
Core Bond Series (Class W) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.80%
Core Bond Series (Class W) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Core Bond Series (Class W) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Core Bond Series (Class Z) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class Z) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Core Bond Series (Class Z) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class Z) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class Z) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.70%
Core Bond Series (Class Z) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Core Bond Series (Class Z) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class Z) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Core Bond Series (Class Z) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Core Bond Series (Class Z) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Core Bond Series (Class Z) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Core Bond Series (Class Z) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.00%
Core Bond Series (Class Z) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Core Bond Series (Class Z) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Core Bond Series (Class Z) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Core Bond Series (Class Z) | U.S. Treasury Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.00%
Core Bond Series (Class Z) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.40%
Core Bond Series (Class Z) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.80%
Core Bond Series (Class Z) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Core Bond Series (Class Z) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Unconstrained Bond Series (Class I) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Unconstrained Bond Series (Class I) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Unconstrained Bond Series (Class I) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Unconstrained Bond Series (Class I) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00%
Unconstrained Bond Series (Class I) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Unconstrained Bond Series (Class I) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Unconstrained Bond Series (Class I) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Unconstrained Bond Series (Class I) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Unconstrained Bond Series (Class I) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.00%
Unconstrained Bond Series (Class I) | Preferred Stock [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Unconstrained Bond Series (Class I) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Unconstrained Bond Series (Class I) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 20.80%
Unconstrained Bond Series (Class I) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Unconstrained Bond Series (Class I) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 21.80%
Unconstrained Bond Series (Class I) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Unconstrained Bond Series (Class I) | Cash, short-term investment, and liabilities, less other assets [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Unconstrained Bond Series (Class I) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Unconstrained Bond Series (Class S) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Unconstrained Bond Series (Class S) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Unconstrained Bond Series (Class S) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Unconstrained Bond Series (Class S) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00%
Unconstrained Bond Series (Class S) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Unconstrained Bond Series (Class S) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Unconstrained Bond Series (Class S) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Unconstrained Bond Series (Class S) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Unconstrained Bond Series (Class S) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.00%
Unconstrained Bond Series (Class S) | Preferred Stock [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Unconstrained Bond Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Unconstrained Bond Series (Class S) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Unconstrained Bond Series (Class S) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 20.80%
Unconstrained Bond Series (Class S) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Unconstrained Bond Series (Class S) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 21.80%
Unconstrained Bond Series (Class S) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Unconstrained Bond Series (Class S) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Unconstrained Bond Series (Class W) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Unconstrained Bond Series (Class W) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Unconstrained Bond Series (Class W) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Unconstrained Bond Series (Class W) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00%
Unconstrained Bond Series (Class W) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Unconstrained Bond Series (Class W) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Unconstrained Bond Series (Class W) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Unconstrained Bond Series (Class W) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Unconstrained Bond Series (Class W) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.00%
Unconstrained Bond Series (Class W) | Preferred Stock [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Unconstrained Bond Series (Class W) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Unconstrained Bond Series (Class W) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Unconstrained Bond Series (Class W) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 20.80%
Unconstrained Bond Series (Class W) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Unconstrained Bond Series (Class W) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 21.80%
Unconstrained Bond Series (Class W) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Unconstrained Bond Series (Class W) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
High Yield Bond Series (Class I) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.50%
High Yield Bond Series (Class I) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.60%
High Yield Bond Series (Class I) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
High Yield Bond Series (Class I) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.90%
High Yield Bond Series (Class I) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 27.00%
High Yield Bond Series (Class I) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.60%
High Yield Bond Series (Class I) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.30%
High Yield Bond Series (Class I) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
High Yield Bond Series (Class I) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
High Yield Bond Series (Class I) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
High Yield Bond Series (Class I) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
High Yield Bond Series (Class I) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
High Yield Bond Series (Class I) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
High Yield Bond Series (Class I) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.00% [1]
High Yield Bond Series (Class I) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
High Yield Bond Series (Class S) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.50%
High Yield Bond Series (Class S) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.60%
High Yield Bond Series (Class S) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
High Yield Bond Series (Class S) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.90%
High Yield Bond Series (Class S) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 27.00%
High Yield Bond Series (Class S) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.60%
High Yield Bond Series (Class S) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.30%
High Yield Bond Series (Class S) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
High Yield Bond Series (Class S) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
High Yield Bond Series (Class S) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
High Yield Bond Series (Class S) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
High Yield Bond Series (Class S) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
High Yield Bond Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
High Yield Bond Series (Class S) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.00% [2]
High Yield Bond Series (Class S) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
High Yield Bond Series (Class W) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.50%
High Yield Bond Series (Class W) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.60%
High Yield Bond Series (Class W) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
High Yield Bond Series (Class W) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.90%
High Yield Bond Series (Class W) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 27.00%
High Yield Bond Series (Class W) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.60%
High Yield Bond Series (Class W) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.30%
High Yield Bond Series (Class W) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
High Yield Bond Series (Class W) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
High Yield Bond Series (Class W) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
High Yield Bond Series (Class W) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
High Yield Bond Series (Class W) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
High Yield Bond Series (Class W) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
High Yield Bond Series (Class W) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.00% [3]
High Yield Bond Series (Class W) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
High Yield Bond Series (Class Z) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.50%
High Yield Bond Series (Class Z) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.60%
High Yield Bond Series (Class Z) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
High Yield Bond Series (Class Z) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.90%
High Yield Bond Series (Class Z) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 27.00%
High Yield Bond Series (Class Z) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.60%
High Yield Bond Series (Class Z) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.30%
High Yield Bond Series (Class Z) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
High Yield Bond Series (Class Z) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
High Yield Bond Series (Class Z) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
High Yield Bond Series (Class Z) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
High Yield Bond Series (Class Z) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
High Yield Bond Series (Class Z) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
High Yield Bond Series (Class Z) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.00% [4]
High Yield Bond Series (Class Z) | Loan Assignments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Diversified Tax Exempt Series (Class A) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Diversified Tax Exempt Series (Class A) | Revenue Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 41.20%
Diversified Tax Exempt Series (Class A) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Diversified Tax Exempt Series (Class A) | General Obligation Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 48.80%
Diversified Tax Exempt Series (Class A) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
Diversified Tax Exempt Series (Class A) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Diversified Tax Exempt Series (Class A) | NEW YORK  
Holdings [Line Items]  
Percent of Net Asset Value 10.80%
Diversified Tax Exempt Series (Class A) | WISCONSIN  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Diversified Tax Exempt Series (Class A) | WASHINGTON  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Diversified Tax Exempt Series (Class A) | ALABAMA  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Diversified Tax Exempt Series (Class A) | TEXAS  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Diversified Tax Exempt Series (Class A) | ILLINOIS  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Diversified Tax Exempt Series (Class A) | DISTRICT OF COLUMBIA  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Diversified Tax Exempt Series (Class A) | FLORIDA  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Diversified Tax Exempt Series (Class A) | TENNESSEE  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Diversified Tax Exempt Series (Class A) | PENNSYLVANIA  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Diversified Tax Exempt Series (Class W) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Diversified Tax Exempt Series (Class W) | Revenue Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 41.20%
Diversified Tax Exempt Series (Class W) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Diversified Tax Exempt Series (Class W) | General Obligation Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 48.80%
Diversified Tax Exempt Series (Class W) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
Diversified Tax Exempt Series (Class W) | U.S. Treasury Notes [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Diversified Tax Exempt Series (Class W) | NEW YORK  
Holdings [Line Items]  
Percent of Net Asset Value 10.80%
Diversified Tax Exempt Series (Class W) | WISCONSIN  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Diversified Tax Exempt Series (Class W) | WASHINGTON  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Diversified Tax Exempt Series (Class W) | ALABAMA  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Diversified Tax Exempt Series (Class W) | TEXAS  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Diversified Tax Exempt Series (Class W) | ILLINOIS  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Diversified Tax Exempt Series (Class W) | DISTRICT OF COLUMBIA  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Diversified Tax Exempt Series (Class W) | FLORIDA  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Diversified Tax Exempt Series (Class W) | TENNESSEE  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Diversified Tax Exempt Series (Class W) | PENNSYLVANIA  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Callodine Equity Income Series (Class I) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Callodine Equity Income Series (Class I) | Common Stocks [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 98.80%
Callodine Equity Income Series (Class I) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Callodine Equity Income Series (Class I) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Callodine Equity Income Series (Class I) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.50%
Callodine Equity Income Series (Class I) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.50%
Callodine Equity Income Series (Class I) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.10%
Callodine Equity Income Series (Class I) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.20%
Callodine Equity Income Series (Class I) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Callodine Equity Income Series (Class I) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Callodine Equity Income Series (Class I) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.50%
Callodine Equity Income Series (Class I) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Callodine Equity Income Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Callodine Equity Income Series (Class S) | Common Stock [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 98.80%
Callodine Equity Income Series (Class S) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Callodine Equity Income Series (Class S) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Callodine Equity Income Series (Class S) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.50%
Callodine Equity Income Series (Class S) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.50%
Callodine Equity Income Series (Class S) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.10%
Callodine Equity Income Series (Class S) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.20%
Callodine Equity Income Series (Class S) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Callodine Equity Income Series (Class S) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Callodine Equity Income Series (Class S) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.50%
Callodine Equity Income Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Callodine Equity Income Series (Class Z) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Callodine Equity Income Series (Class Z) | Common Stock [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 98.80%
Callodine Equity Income Series (Class Z) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Callodine Equity Income Series (Class Z) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Callodine Equity Income Series (Class Z) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.50%
Callodine Equity Income Series (Class Z) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.50%
Callodine Equity Income Series (Class Z) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.10%
Callodine Equity Income Series (Class Z) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.20%
Callodine Equity Income Series (Class Z) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Callodine Equity Income Series (Class Z) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Callodine Equity Income Series (Class Z) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.50%
Callodine Equity Income Series (Class Z) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Credit Series (Class I) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Credit Series (Class I) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Credit Series (Class I) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Credit Series (Class I) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Credit Series (Class I) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.10%
Credit Series (Class I) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Credit Series (Class I) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Credit Series (Class I) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Credit Series (Class I) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
Credit Series (Class I) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
Credit Series (Class I) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Credit Series (Class I) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.60%
Credit Series (Class I) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Credit Series (Class I) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Credit Series (Class I) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Credit Series (Class I) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.00%
Credit Series (Class I) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 21.90%
Credit Series (Class I) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Credit Series (Class S) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Credit Series (Class S) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Credit Series (Class S) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Credit Series (Class S) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Credit Series (Class S) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.10%
Credit Series (Class S) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Credit Series (Class S) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Credit Series (Class S) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Credit Series (Class S) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
Credit Series (Class S) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
Credit Series (Class S) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Credit Series (Class S) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.60%
Credit Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Credit Series (Class S) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Credit Series (Class S) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Credit Series (Class S) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.00%
Credit Series (Class S) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 21.90%
Credit Series (Class S) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Credit Series (Class W) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Credit Series (Class W) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Credit Series (Class W) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Credit Series (Class W) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Credit Series (Class W) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.10%
Credit Series (Class W) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Credit Series (Class W) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Credit Series (Class W) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.10%
Credit Series (Class W) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
Credit Series (Class W) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
Credit Series (Class W) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Credit Series (Class W) | Asset-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.60%
Credit Series (Class W) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
Credit Series (Class W) | Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Credit Series (Class W) | Exchange Traded Funds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Credit Series (Class W) | U.S. Government Agencies [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.00%
Credit Series (Class W) | Commercial Mortgage-Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 21.90%
Credit Series (Class W) | Foreign Government Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Systematic High Yield Bond Series (Class I) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Systematic High Yield Bond Series (Class I) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.30%
Systematic High Yield Bond Series (Class I) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Systematic High Yield Bond Series (Class I) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Systematic High Yield Bond Series (Class I) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.80%
Systematic High Yield Bond Series (Class I) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Systematic High Yield Bond Series (Class I) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
Systematic High Yield Bond Series (Class I) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Systematic High Yield Bond Series (Class I) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.90%
Systematic High Yield Bond Series (Class I) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
Systematic High Yield Bond Series (Class I) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Systematic High Yield Bond Series (Class I) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
Systematic High Yield Bond Series (Class S) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Systematic High Yield Bond Series (Class S) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.30%
Systematic High Yield Bond Series (Class S) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Systematic High Yield Bond Series (Class S) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Systematic High Yield Bond Series (Class S) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.80%
Systematic High Yield Bond Series (Class S) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Systematic High Yield Bond Series (Class S) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
Systematic High Yield Bond Series (Class S) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Systematic High Yield Bond Series (Class S) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.90%
Systematic High Yield Bond Series (Class S) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
Systematic High Yield Bond Series (Class S) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Systematic High Yield Bond Series (Class S) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
Systematic High Yield Bond Series (Class W) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Systematic High Yield Bond Series (Class W) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.30%
Systematic High Yield Bond Series (Class W) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Systematic High Yield Bond Series (Class W) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Systematic High Yield Bond Series (Class W) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.80%
Systematic High Yield Bond Series (Class W) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Systematic High Yield Bond Series (Class W) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
Systematic High Yield Bond Series (Class W) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Systematic High Yield Bond Series (Class W) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.90%
Systematic High Yield Bond Series (Class W) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
Systematic High Yield Bond Series (Class W) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Systematic High Yield Bond Series (Class W) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
Systematic High Yield Bond Series (Class Z) | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Systematic High Yield Bond Series (Class Z) | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.30%
Systematic High Yield Bond Series (Class Z) | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Systematic High Yield Bond Series (Class Z) | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Systematic High Yield Bond Series (Class Z) | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.80%
Systematic High Yield Bond Series (Class Z) | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Systematic High Yield Bond Series (Class Z) | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
Systematic High Yield Bond Series (Class Z) | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Systematic High Yield Bond Series (Class Z) | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.90%
Systematic High Yield Bond Series (Class Z) | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
Systematic High Yield Bond Series (Class Z) | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Systematic High Yield Bond Series (Class Z) | Cash, short-term investment, and other assets, less liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
[1] Less than 0.1%
[2] Less than 0.1%
[3] Less than 0.1%
[4] Less than 0.1%