| Form N-CSR Cover | 6 Months Ended |
| Jun. 30, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| Amendment Flag | false |
| Registrant Name | MASSACHUSETTS INVESTORS TRUST |
| Entity Central Index Key | 0000063091 |
| Document Period End Date | Jun. 30, 2024 |
| Shareholder Report | 6 Months Ended |
| Jun. 30, 2024 USD ($) Holding | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| Amendment Flag | false |
| Registrant Name | MASSACHUSETTS INVESTORS TRUST |
| Entity Central Index Key | 0000063091 |
| Document Period End Date | Jun. 30, 2024 |
| C000002037 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class A |
| Trading Symbol | MITTX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment A $ 0.70 % |
| Expenses Paid, Amount | $ 37 |
| Expense Ratio, Percent | 0.70% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002042 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class B |
| Trading Symbol | MITBX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment B $ 1.45 % |
| Expenses Paid, Amount | $ 77 |
| Expense Ratio, Percent | 1.45% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002043 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class C |
| Trading Symbol | MITCX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment C $ 1.45 % |
| Expenses Paid, Amount | $ 77 |
| Expense Ratio, Percent | 1.45% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002044 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class I |
| Trading Symbol | MITIX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment I $ 0.45 % |
| Expenses Paid, Amount | $ 24 |
| Expense Ratio, Percent | 0.45% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002046 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class R1 |
| Trading Symbol | MITGX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment R1 $ 1.45 % |
| Expenses Paid, Amount | $ 77 |
| Expense Ratio, Percent | 1.45% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002048 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class R2 |
| Trading Symbol | MIRTX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment R2 $ 0.95 % |
| Expenses Paid, Amount | $ 51 |
| Expense Ratio, Percent | 0.95% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002049 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class R3 |
| Trading Symbol | MITHX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment R3 $ 0.70 % |
| Expenses Paid, Amount | $ 37 |
| Expense Ratio, Percent | 0.70% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000002038 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class R4 |
| Trading Symbol | MITDX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment R4 $ 0.45 % |
| Expenses Paid, Amount | $ 24 |
| Expense Ratio, Percent | 0.45% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| C000113374 [Member] | |
| Shareholder Report [Line Items] | |
| Fund Name | Massachusetts Investors Trust |
| Class Name | Class R6 |
| Trading Symbol | MITJX |
| Annual or Semi-Annual Statement [Text Block] | This semiannual shareholder report |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at funds.mfs.com |
| Additional Information Phone Number | 1‑800‑225‑2606 |
| Additional Information Email | orderliterature@mfs.com |
| Additional Information Website | funds.mfs.com |
| Expenses [Text Block] | FUND EXPENSES What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment R6 $ 0.37 % |
| Expenses Paid, Amount | $ 20 |
| Expense Ratio, Percent | 0.37% |
| Net Assets | $ 6,904,368,016 |
| Holdings Count | Holding | 65 |
| Investment Company Portfolio Turnover | 11% |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 6/30/24 Net Assets ($): 6,904,368,016 Portfolio Turnover (%): 11 Total Number of Holdings: 65 Where the fund holds derivatives, they are not included in the total number of portfolio holdings. |
| Holdings [Text Block] | PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 6/30/24) Portfolio structure Equities 99.1 % Money Market Funds 0.9 % GICS equity sectors Information Technology 30.9 % Financials 15.0 % Health Care 12.7 % Industrials 9.1 % Communication Services 7.3 % Consumer Staples 6.8 % Consumer Discretionary 6.7 % Energy 3.7 % Materials 3.0 % Utilities 2.2 % Real Estate 1.7 % Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % MFS uses the Global Industry Classification Standard (GICS ® |
| Largest Holdings [Text Block] | Top ten holdings Microsoft Corp. 9.3 % NVIDIA Corp. 6.3 % Alphabet, Inc., "A" 6.1 % Amazon.com, Inc. 4.4 % Apple, Inc. 3.9 % JPMorgan Chase & Co. 2.8 % ConocoPhillips 2.3 % Visa, Inc., "A" 2.2 % Howmet Aerospace, Inc. 2.0 % Mastercard, Inc., "A" 1.8 % |
| Shareholder Report, Holdings (Details) | Jun. 30, 2024 |
| C000002037 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002037 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002037 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002037 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002037 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002037 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002037 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002037 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002037 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002037 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002037 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002037 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002037 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002037 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002037 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002037 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002037 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002037 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002037 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002037 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002037 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002037 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002037 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 90% |
| C000002042 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002042 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002042 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002042 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002042 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002042 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002042 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002042 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002042 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002042 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002042 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002042 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002042 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002042 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002042 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002042 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002042 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002042 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002042 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002042 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002042 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002042 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002042 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000002043 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002043 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002043 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002043 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002043 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002043 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002043 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002043 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002043 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002043 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002043 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002043 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002043 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002043 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002043 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002043 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002043 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002043 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002043 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002043 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002043 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002043 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002043 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000002044 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002044 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002044 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002044 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002044 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002044 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002044 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002044 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002044 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002044 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002044 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002044 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002044 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002044 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002044 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002044 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002044 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002044 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002044 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002044 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002044 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002044 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002044 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000002046 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002046 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002046 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002046 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002046 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002046 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002046 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002046 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002046 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002046 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002046 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002046 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002046 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002046 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002046 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002046 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002046 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002046 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002046 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002046 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002046 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002046 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002046 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000002048 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002048 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002048 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002048 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002048 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002048 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002048 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002048 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002048 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002048 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002048 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002048 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002048 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002048 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002048 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002048 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002048 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002048 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002048 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002048 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002048 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002048 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002048 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000002049 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002049 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002049 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002049 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002049 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002049 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002049 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002049 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002049 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002049 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002049 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002049 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002049 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002049 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002049 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002049 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002049 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002049 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002049 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002049 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002049 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002049 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002049 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000002038 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000002038 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000002038 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000002038 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000002038 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000002038 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000002038 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000002038 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002038 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000002038 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000002038 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000002038 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000002038 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000002038 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000002038 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000002038 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000002038 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000002038 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000002038 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000002038 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000002038 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000002038 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000002038 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
| C000113374 [Member] | Microsoft Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.30% |
| C000113374 [Member] | NVIDIA Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.30% |
| C000113374 [Member] | Alphabet Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.10% |
| C000113374 [Member] | Amazon com Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.40% |
| C000113374 [Member] | Apple Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.90% |
| C000113374 [Member] | JPMorgan Chase And Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000113374 [Member] | ConocoPhillips [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.30% |
| C000113374 [Member] | Visa Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000113374 [Member] | Howmet Aerospace Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000113374 [Member] | Mastercard Inc A [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.80% |
| C000113374 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.70% |
| C000113374 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.70% |
| C000113374 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000113374 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.30% |
| C000113374 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.70% |
| C000113374 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.80% |
| C000113374 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.10% |
| C000113374 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000113374 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3% |
| C000113374 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000113374 [Member] | Financials [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15% |
| C000113374 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 99.10% |
| C000113374 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.90% |
