v3.26.1
Shareholder Report, Holdings (Details)
Jan. 31, 2026
C000007089 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
C000007089 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
C000007089 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 13.20%
C000007089 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
C000007089 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 80.10%
C000007089 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
C000007090 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 2.70%
C000007090 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
C000007090 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 13.20%
C000007090 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
C000007090 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 80.10%
C000007090 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
C000007092 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
C000007092 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 13.00%
C000007092 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
C000007092 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
C000007092 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 10.40%
C000007092 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 10.10%
C000007092 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
C000007092 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000007092 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 9.60%
C000007092 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000007092 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000007092 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
C000007092 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 9.00%
C000007093 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
C000007093 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 13.00%
C000007093 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
C000007093 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
C000007093 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 10.40%
C000007093 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 10.10%
C000007093 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
C000007093 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000007093 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 9.60%
C000007093 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000007093 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000007093 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
C000007093 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 9.00%
C000007097 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
C000007097 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
C000007097 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000007097 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 6.50%
C000007097 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 30.50%
C000007097 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.50%
C000007097 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000007097 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
C000007097 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000007097 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007097 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 8.40%
C000007097 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
C000007097 | Communication Services  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
C000007098 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
C000007098 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
C000007098 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000007098 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 6.50%
C000007098 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 30.50%
C000007098 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.50%
C000007098 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000007098 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
C000007098 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000007098 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007098 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 8.40%
C000007098 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
C000007098 | Communication Services  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
C000007099 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000007099 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000007099 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
C000007099 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000007099 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 81.60%
C000007099 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
C000007100 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000007100 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000007100 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
C000007100 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000007100 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 81.60%
C000007100 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 2.20%
C000007101 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
C000007101 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
C000007101 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000007101 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000007101 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
C000007101 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 17.80%
C000007101 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 11.60%
C000007101 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007101 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000007101 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
C000007101 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
C000007101 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
C000007101 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 16.80%
C000007102 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
C000007102 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
C000007102 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000007102 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000007102 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
C000007102 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 17.80%
C000007102 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 11.60%
C000007102 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007102 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000007102 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
C000007102 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
C000007102 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
C000007102 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 16.80%
C000007103 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
C000007103 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000007103 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
C000007103 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 86.90%
C000007103 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 1.70%
C000007103 | Conventional Mortgage-Backed Securities-Liability for Sale Commitments  
Holdings [Line Items]  
Percent of Net Asset Value (2.10%)
C000007104 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
C000007104 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000007104 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
C000007104 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 86.90%
C000007104 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 1.70%
C000007104 | Conventional Mortgage-Backed Securities-Liability for Sale Commitments  
Holdings [Line Items]  
Percent of Net Asset Value (2.10%)
C000007105 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 16.90%
C000007105 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
C000007105 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 43.30%
C000007105 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007105 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 12.00%
C000007105 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
C000007105 | Conventional Mortgage-Backed Securities-Liability for Sale Commitments  
Holdings [Line Items]  
Percent of Net Asset Value (1.30%)
C000007106 | Agency Bonds and Notes  
Holdings [Line Items]  
Percent of Net Asset Value 16.90%
C000007106 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
C000007106 | Conventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 43.30%
C000007106 | Nonconventional Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007106 | U.S. Government Securities  
Holdings [Line Items]  
Percent of Net Asset Value 12.00%
C000007106 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
C000007106 | Conventional Mortgage-Backed Securities-Liability for Sale Commitments  
Holdings [Line Items]  
Percent of Net Asset Value (1.30%)
C000007107 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
C000007107 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000007107 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007107 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
C000007107 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007107 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 30.60%
C000007107 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
C000007107 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007107 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000007107 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000007107 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 5.20%
C000007107 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007107 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 18.70%
C000007108 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
C000007108 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000007108 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007108 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
C000007108 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007108 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 30.60%
C000007108 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
C000007108 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007108 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000007108 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000007108 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 5.20%
C000007108 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007108 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 18.70%
C000007109 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
C000007109 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000007109 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007109 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
C000007109 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007109 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 30.60%
C000007109 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
C000007109 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
C000007109 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000007109 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000007109 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 5.20%
C000007109 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 6.10%
C000007109 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 18.70%
C000151976 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 30.10%
C000151976 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 8.70%
C000151976 | Corporate Bonds  
Holdings [Line Items]  
Percent of Net Asset Value 57.20%
C000151976 | Sovereign Bonds  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
C000151976 | U.S. Government and Agency Obligations  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
C000151975 | Asset-Backed/Commercial Mortgage-Backed Securities  
Holdings [Line Items]  
Percent of Net Asset Value 30.10%
C000151975 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 8.70%
C000151975 | Corporate Bonds  
Holdings [Line Items]  
Percent of Net Asset Value 57.20%
C000151975 | Sovereign Bonds  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
C000151975 | U.S. Government and Agency Obligations  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
C000264003 | Other Assets and Liabilities, Net  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
C000264003 | Communications  
Holdings [Line Items]  
Percent of Net Asset Value 12.30%
C000264003 | Consumer Discretionary  
Holdings [Line Items]  
Percent of Net Asset Value 14.30%
C000264003 | Consumer Staples  
Holdings [Line Items]  
Percent of Net Asset Value 5.70%
C000264003 | Energy  
Holdings [Line Items]  
Percent of Net Asset Value 11.00%
C000264003 | Financials  
Holdings [Line Items]  
Percent of Net Asset Value 9.70%
C000264003 | Health Care  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
C000264003 | Industrials  
Holdings [Line Items]  
Percent of Net Asset Value 7.40%
C000264003 | Materials  
Holdings [Line Items]  
Percent of Net Asset Value 11.70%
C000264003 | Real Estate  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
C000264003 | Technology  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
C000264003 | Utilities  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000264003 | Asset Other Line  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%