v3.26.1
Shareholder Report, Holdings (Details)
Mar. 31, 2026
C000006083 [Member] | Casey s General Stores Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [1]
C000006083 [Member] | ITT Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [1]
C000006083 [Member] | Coherent Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [1]
C000006083 [Member] | Reinsurance Group of America Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [1]
C000006083 [Member] | EMCOR Group Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [1]
C000006083 [Member] | Lumentum Holdings Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90% [1]
C000006083 [Member] | Ciena Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [1]
C000006083 [Member] | Cullen Frost Bankers Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [1]
C000006083 [Member] | Comfort Systems U S A Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20% [1]
C000006083 [Member] | Sandisk Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30% [1]
C000006083 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40% [2]
C000006083 [Member] | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00% [2]
C000006083 [Member] | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.10% [2]
C000006083 [Member] | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.70% [2]
C000006083 [Member] | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30% [2]
C000006083 [Member] | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.80% [2]
C000006083 [Member] | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50% [2]
C000006083 [Member] | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [2]
C000006083 [Member] | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.70% [2]
C000006083 [Member] | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.90% [2]
C000006083 [Member] | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [2]
C000006083 [Member] | Liabilities in Excess of Other Assets [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (2.00%) [2]
C000006083 [Member] | Short-Term Investments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20% [2]
C000199765 [Member] | Casey s General Stores Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [3]
C000199765 [Member] | ITT Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [3]
C000199765 [Member] | Coherent Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [3]
C000199765 [Member] | Reinsurance Group of America Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [3]
C000199765 [Member] | EMCOR Group Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [3]
C000199765 [Member] | Lumentum Holdings Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90% [3]
C000199765 [Member] | Ciena Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [3]
C000199765 [Member] | Cullen Frost Bankers Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [3]
C000199765 [Member] | Comfort Systems U S A Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20% [3]
C000199765 [Member] | Sandisk Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30% [3]
C000199765 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40% [4]
C000199765 [Member] | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00% [4]
C000199765 [Member] | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.10% [4]
C000199765 [Member] | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.70% [4]
C000199765 [Member] | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30% [4]
C000199765 [Member] | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.80% [4]
C000199765 [Member] | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50% [4]
C000199765 [Member] | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [4]
C000199765 [Member] | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.70% [4]
C000199765 [Member] | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.90% [4]
C000199765 [Member] | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [4]
C000199765 [Member] | Liabilities in Excess of Other Assets [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (2.00%) [4]
C000199765 [Member] | Short-Term Investments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20% [4]
C000006081 [Member] | Casey s General Stores Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [5]
C000006081 [Member] | ITT Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [5]
C000006081 [Member] | Coherent Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [5]
C000006081 [Member] | Reinsurance Group of America Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [5]
C000006081 [Member] | EMCOR Group Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [5]
C000006081 [Member] | Lumentum Holdings Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90% [5]
C000006081 [Member] | Ciena Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [5]
C000006081 [Member] | Cullen Frost Bankers Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [5]
C000006081 [Member] | Comfort Systems U S A Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20% [5]
C000006081 [Member] | Sandisk Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30% [5]
C000006081 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40% [6]
C000006081 [Member] | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00% [6]
C000006081 [Member] | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.10% [6]
C000006081 [Member] | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.70% [6]
C000006081 [Member] | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30% [6]
C000006081 [Member] | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.80% [6]
C000006081 [Member] | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50% [6]
C000006081 [Member] | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [6]
C000006081 [Member] | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.70% [6]
C000006081 [Member] | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.90% [6]
C000006081 [Member] | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [6]
C000006081 [Member] | Liabilities in Excess of Other Assets [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (2.00%) [6]
C000006081 [Member] | Short-Term Investments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20% [6]
C000006079 [Member] | Casey s General Stores Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [7]
C000006079 [Member] | ITT Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [7]
C000006079 [Member] | Coherent Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [7]
C000006079 [Member] | Reinsurance Group of America Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [7]
C000006079 [Member] | EMCOR Group Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [7]
C000006079 [Member] | Lumentum Holdings Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90% [7]
C000006079 [Member] | Ciena Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [7]
C000006079 [Member] | Cullen Frost Bankers Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [7]
C000006079 [Member] | Comfort Systems U S A Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20% [7]
C000006079 [Member] | Sandisk Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30% [7]
C000006079 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40% [8]
C000006079 [Member] | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00% [8]
C000006079 [Member] | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.10% [8]
C000006079 [Member] | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.70% [8]
C000006079 [Member] | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30% [8]
C000006079 [Member] | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.80% [8]
C000006079 [Member] | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50% [8]
C000006079 [Member] | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [8]
C000006079 [Member] | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.70% [8]
C000006079 [Member] | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.90% [8]
C000006079 [Member] | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [8]
C000006079 [Member] | Liabilities in Excess of Other Assets [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (2.00%) [8]
C000006079 [Member] | Short-Term Investments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20% [8]
C000006082 [Member] | Casey s General Stores Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [9]
C000006082 [Member] | ITT Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [9]
C000006082 [Member] | Coherent Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [9]
C000006082 [Member] | Reinsurance Group of America Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [9]
C000006082 [Member] | EMCOR Group Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.70% [9]
C000006082 [Member] | Lumentum Holdings Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 0.90% [9]
C000006082 [Member] | Ciena Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [9]
C000006082 [Member] | Cullen Frost Bankers Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.00% [9]
C000006082 [Member] | Comfort Systems U S A Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20% [9]
C000006082 [Member] | Sandisk Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.30% [9]
C000006082 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.40% [10]
C000006082 [Member] | Materials Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.00% [10]
C000006082 [Member] | Information Technology Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.10% [10]
C000006082 [Member] | Industrial Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 22.70% [10]
C000006082 [Member] | Consumer Staples Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.30% [10]
C000006082 [Member] | Consumer Discretionary Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.80% [10]
C000006082 [Member] | Communications Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.50% [10]
C000006082 [Member] | Real Estate Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [10]
C000006082 [Member] | Healthcare Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.70% [10]
C000006082 [Member] | Financial Services Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.90% [10]
C000006082 [Member] | Energy Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [10]
C000006082 [Member] | Liabilities in Excess of Other Assets [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (2.00%) [10]
C000006082 [Member] | Short-Term Investments [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.20% [10]
[1] Excludes short-term securities.
[2] For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
[3] Excludes short-term securities.
[4] For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
[5]
Excludes short-term securities.
[6]
For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
[7] Excludes short-term securities.
[8] For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
[9] Excludes short-term securities.
[10] For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.