v3.25.2
Shareholder Report, Holdings (Details)
Jun. 30, 2025
C000007057 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 36.70%
C000007057 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
C000007057 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 57.30%
C000007057 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000007057 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000046841 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 36.70%
C000046841 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
C000046841 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 57.30%
C000046841 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000046841 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000007058 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 36.70%
C000007058 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
C000007058 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 57.30%
C000007058 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000007058 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000024520 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 36.70%
C000024520 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
C000024520 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 57.30%
C000024520 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000024520 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000105308 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 36.70%
C000105308 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
C000105308 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 57.30%
C000105308 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000105308 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000046842 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 42.70%
C000046842 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000046842 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 50.90%
C000046842 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000046842 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
C000209800 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 42.70%
C000209800 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000209800 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 50.90%
C000209800 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000209800 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
C000024522 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 42.70%
C000024522 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000024522 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 50.90%
C000024522 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000024522 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
C000105309 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 42.70%
C000105309 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
C000105309 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 50.90%
C000105309 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000105309 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
C000007060 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.30%
C000007060 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
C000007060 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.60%
C000007060 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000007060 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000046843 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.30%
C000046843 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
C000046843 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.60%
C000046843 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000046843 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000007061 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.30%
C000007061 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
C000007061 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.60%
C000007061 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000007061 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000105310 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.30%
C000105310 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
C000105310 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.60%
C000105310 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000105310 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000105311 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.30%
C000105311 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
C000105311 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.60%
C000105311 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
C000105311 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
C000007062 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.40%
C000007062 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000007062 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 67.80%
C000007062 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000007062 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000007062 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000046844 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.40%
C000046844 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000046844 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 67.80%
C000046844 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000046844 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000046844 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000007063 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.40%
C000007063 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000007063 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 67.80%
C000007063 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000007063 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000007063 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000007064 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.40%
C000007064 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000007064 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 67.80%
C000007064 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000007064 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000007064 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000081425 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.40%
C000081425 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000081425 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 67.80%
C000081425 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000081425 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000081425 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000170279 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.40%
C000170279 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000170279 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 67.80%
C000170279 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000170279 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
C000170279 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
C000054349 [Member] | Zero To 5 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 49.10%
C000054349 [Member] | Five To 10 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 37.00%
C000054349 [Member] | Ten To 15 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
C000054349 [Member] | Fifteen To 20 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000054349 [Member] | Twenty To 25 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000054349 [Member] | Over 25 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
C000054349 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
C000054350 [Member] | Zero To 5 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 49.10%
C000054350 [Member] | Five To 10 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 37.00%
C000054350 [Member] | Ten To 15 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
C000054350 [Member] | Fifteen To 20 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000054350 [Member] | Twenty To 25 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000054350 [Member] | Over 25 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
C000054350 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
C000054351 [Member] | Zero To 5 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 49.10%
C000054351 [Member] | Five To 10 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 37.00%
C000054351 [Member] | Ten To 15 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
C000054351 [Member] | Fifteen To 20 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000054351 [Member] | Twenty To 25 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000054351 [Member] | Over 25 Years [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
C000054351 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
C000075027 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.00%
C000075027 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000075027 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.20%
C000075027 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000075027 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
C000075027 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
C000075028 [Member] | Corporate Bond Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 25.00%
C000075028 [Member] | Taxable Municipal Bonds [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
C000075028 [Member] | US Government Corporations and Agencies Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 68.20%
C000075028 [Member] | Sovereign Debt [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30%
C000075028 [Member] | Other Assets and Liabilities Net [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
C000075028 [Member] | Asset Backed Commercial Mortgage Backed Securities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%