Shareholder Report, Holdings (Details)

Apr. 30, 2026

C000000765 [Member] | Financial Services Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

7.80%

C000000765 [Member] | Energy Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.70%

C000000765 [Member] | Industrial Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.90%

C000000765 [Member] | Communications Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.20%

C000000765 [Member] | Utilities Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.50%

C000000765 [Member] | Technology Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.00%

C000000765 [Member] | Government Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

49.50%

C000000765 [Member] | Investment Companies Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

5.60%

C000000765 [Member] | Consumer Non cyclical [Member]

Holdings [Line Items]

Percent of Net Asset Value

4.20%

C000000765 [Member] | Net Other Assets and Liabilities Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

(4.10%)

C000000765 [Member] | Consumer Cyclical [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.50%

C000000765 [Member] | Net Other Assets and Liabilities [Member]

Holdings [Line Items]

Percent of Net Asset Value

(5.00%)

C000000765 [Member] | Asset-Backed Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.40%

C000000765 [Member] | US Treasury Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

45.50%

C000000765 [Member] | Commercial Mortgage-Backed Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.60%

C000000765 [Member] | US Government Corporations and Agencies Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.60%

C000000765 [Member] | U S Government Agencies Mortgage Backed Short [Member]

Holdings [Line Items]

Percent of Net Asset Value

(2.90%)

C000000765 [Member] | Municipal Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.60%

C000000765 [Member] | U S Government Agencies Collateralized Municipal Backed [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.80%

C000000765 [Member] | Foreign Governmental [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.50%

C000000765 [Member] | Mortgage Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

25.20%

C000000765 [Member] | Investment Companies [Member]

Holdings [Line Items]

Percent of Net Asset Value

5.60%

C000000765 [Member] | Corporate Bonds and Notes [Member]

Holdings [Line Items]

Percent of Net Asset Value

25.60%

C000000765 [Member] | U S Government Agencies Mortgage Backed Long [Member]

Holdings [Line Items]

Percent of Net Asset Value

26.70%

C000000766 [Member] | Financial Services Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

7.80%

C000000766 [Member] | Energy Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.70%

C000000766 [Member] | Industrial Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.90%

C000000766 [Member] | Communications Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.20%

C000000766 [Member] | Utilities Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.50%

C000000766 [Member] | Technology Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.00%

C000000766 [Member] | Government Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

49.50%

C000000766 [Member] | Investment Companies Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

5.60%

C000000766 [Member] | Consumer Non cyclical [Member]

Holdings [Line Items]

Percent of Net Asset Value

4.20%

C000000766 [Member] | Net Other Assets and Liabilities Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

(4.10%)

C000000766 [Member] | Consumer Cyclical [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.50%

C000000766 [Member] | Net Other Assets and Liabilities [Member]

Holdings [Line Items]

Percent of Net Asset Value

(5.00%)

C000000766 [Member] | Asset-Backed Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.40%

C000000766 [Member] | US Treasury Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

45.50%

C000000766 [Member] | Commercial Mortgage-Backed Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.60%

C000000766 [Member] | US Government Corporations and Agencies Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.60%

C000000766 [Member] | U S Government Agencies Mortgage Backed Short [Member]

Holdings [Line Items]

Percent of Net Asset Value

(2.90%)

C000000766 [Member] | Municipal Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.60%

C000000766 [Member] | U S Government Agencies Collateralized Municipal Backed [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.80%

C000000766 [Member] | Foreign Governmental [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.50%

C000000766 [Member] | Mortgage Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

25.20%

C000000766 [Member] | Investment Companies [Member]

Holdings [Line Items]

Percent of Net Asset Value

5.60%

C000000766 [Member] | Corporate Bonds and Notes [Member]

Holdings [Line Items]

Percent of Net Asset Value

25.60%

C000000766 [Member] | U S Government Agencies Mortgage Backed Long [Member]

Holdings [Line Items]

Percent of Net Asset Value

26.70%

C000000734 [Member] | Alphabet Inc Cl A [Member]

Holdings [Line Items]

Percent of Net Asset Value

3.60%

^[1]

C000000734 [Member] | Alphabet Inc Cl C [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.90%

^[1]

C000000734 [Member] | Meta Platforms Inc Cl A [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.10%

^[1]

C000000734 [Member] | Berkshire Hathaway Inc Cl B [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.40%

^[1]

C000000734 [Member] | Apple Inc [Member]

Holdings [Line Items]

Percent of Net Asset Value

6.40%

^[1]

C000000734 [Member] | Microsoft Corp [Member]

Holdings [Line Items]

Percent of Net Asset Value

4.90%

^[1]

C000000734 [Member] | NVIDIA Corp [Member]

Holdings [Line Items]

Percent of Net Asset Value

7.80%

^[1]

C000000734 [Member] | Amazon com Inc [Member]

Holdings [Line Items]

Percent of Net Asset Value

4.20%

^[1]

C000000734 [Member] | Broadcom Inc [Member]

Holdings [Line Items]

Percent of Net Asset Value

3.20%

^[1]

C000000734 [Member] | Tesla Inc [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.70%

^[1]

C000000734 [Member] | Real Estate Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.90%

C000000734 [Member] | Financial Services Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

11.90%

C000000734 [Member] | Healthcare Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

8.40%

C000000734 [Member] | Energy Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

3.50%

C000000734 [Member] | Consumer Staples Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

4.90%

C000000734 [Member] | Industrial Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

8.80%

C000000734 [Member] | Information Technology Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

34.70%

C000000734 [Member] | Materials Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

1.90%

C000000734 [Member] | Communications Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

10.90%

C000000734 [Member] | Consumer Discretionary Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

9.90%

C000000734 [Member] | Utilities Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.30%

C000000734 [Member] | Net Other Assets and Liabilities [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.90%

[1]	Excludes money market funds or other short-term securities held for the investment of cash and cash collateral for securities loaned, if any.