| Form N-CSR Cover | 6 Months Ended |
| Aug. 31, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| Amendment Flag | false |
| Registrant Name | MFS SERIES TRUST XIII |
| Entity Central Index Key | 0000356349 |
| Document Period End Date | Aug. 31, 2024 |
| Shareholder Report | 6 Months Ended | |
| Aug. 31, 2024 USD ($) Holding | ||
| Shareholder Report [Line Items] | ||
| Document Type | N-CSRS | |
| Amendment Flag | false | |
| Registrant Name | MFS SERIES TRUST XIII | |
| Entity Central Index Key | 0000356349 | |
| Document Period End Date | Aug. 31, 2024 | |
| C000002007 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class A | |
| Trading Symbol | MFGSX | |
| 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 (annualized) A $ 0.78 % | |
| Expenses Paid, Amount | $ 40 | |
| Expense Ratio, Percent | 0.78% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002012 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class B | |
| Trading Symbol | MFGBX | |
| 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 (annualized) B $ 1.53 % | |
| Expenses Paid, Amount | $ 79 | |
| Expense Ratio, Percent | 1.53% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002013 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class C | |
| Trading Symbol | MFGDX | |
| 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 (annualized) C $ 1.53 % | |
| Expenses Paid, Amount | $ 79 | |
| Expense Ratio, Percent | 1.53% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002006 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class I | |
| Trading Symbol | MGSIX | |
| 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 (annualized) I $ 0.53 % | |
| Expenses Paid, Amount | $ 27 | |
| Expense Ratio, Percent | 0.53% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002015 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class R1 | |
| Trading Symbol | MFGGX | |
| 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 (annualized) R1 $ 1.53 % | |
| Expenses Paid, Amount | $ 79 | |
| Expense Ratio, Percent | 1.53% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002017 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class R2 | |
| Trading Symbol | MGVSX | |
| 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 (annualized) R2 $ 1.03 % | |
| Expenses Paid, Amount | $ 53 | |
| Expense Ratio, Percent | 1.03% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002018 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® GovernmentSecurities Fund | |
| Class Name | Class R3 | |
| Trading Symbol | MFGHX | |
| 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 (annualized) R3 $ 0.78 % | |
| Expenses Paid, Amount | $ 40 | |
| Expense Ratio, Percent | 0.78% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000002008 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class R4 | |
| Trading Symbol | MFGJX | |
| 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 (annualized) R4 $ 0.53 % | |
| Expenses Paid, Amount | $ 27 | |
| Expense Ratio, Percent | 0.53% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000117927 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Government Securities Fund | |
| Class Name | Class R6 | |
| Trading Symbol | MFGKX | |
| 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 (annualized) R6 $ 0.42 % | |
| Expenses Paid, Amount | $ 22 | |
| Expense Ratio, Percent | 0.42% | |
| Net Assets | $ 2,072,366,580 | |
| Holdings Count | Holding | 775 | |
| Investment Company Portfolio Turnover | 107% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,072,366,580 Average Effective Maturity (yrs): 6.8 Total Number of Holdings: 775 Average Effective Duration (yrs): 5.9 Portfolio Turnover Rate (%): 107 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 8/31/24) Portfolio structure Fixed Income 95.3 % Money Market Funds 4.7 % Composition including fixed income credit quality AAA 7.1 % AA 1.1 % A 0.7 % BBB 0.1 % U.S. Government 32.4 % Federal Agencies 53.9 % Money Market Funds 4.7 % Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000100956 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class A | |
| Trading Symbol | NDVAX | |
| 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 (annualized) A $ 1.19 % | |
| Expenses Paid, Amount | $ 63 | |
| Expense Ratio, Percent | 1.19% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100957 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class B | |
| Trading Symbol | NDVBX | |
| 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 (annualized) B $ 1.94 % | |
| Expenses Paid, Amount | $ 103 | |
| Expense Ratio, Percent | 1.94% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100958 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class C | |
| Trading Symbol | NDVCX | |
| 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 (annualized) C $ 1.94 % | |
| Expenses Paid, Amount | $ 103 | |
| Expense Ratio, Percent | 1.94% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100959 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class I | |
| Trading Symbol | NDVIX | |
| 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 (annualized) I $ 0.94 % | |
| Expenses Paid, Amount | $ 50 | |
| Expense Ratio, Percent | 0.94% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100960 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class R1 | |
| Trading Symbol | NDVRX | |
| 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 (annualized) R1 $ 1.94 % | |
| Expenses Paid, Amount | $ 103 | |
| Expense Ratio, Percent | 1.94% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100961 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class R2 | |
| Trading Symbol | NDVSX | |
| 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 (annualized) R2 $ 1.44 % | |
| Expenses Paid, Amount | $ 77 | |
| Expense Ratio, Percent | 1.44% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100962 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class R3 | |
| Trading Symbol | NDVTX | |
| 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 (annualized) R3 $ 1.19 % | |
| Expenses Paid, Amount | $ 63 | |
| Expense Ratio, Percent | 1.19% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000100963 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class R4 | |
| Trading Symbol | NDVUX | |
| 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 (annualized) R4 $ 0.94 % | |
| Expenses Paid, Amount | $ 50 | |
| Expense Ratio, Percent | 0.94% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000117930 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® New Discovery Value Fund | |
| Class Name | Class R6 | |
| Trading Symbol | NDVVX | |
| 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 (annualized) R6 $ 0.85 % | |
| Expenses Paid, Amount | $ 45 | |
| Expense Ratio, Percent | 0.85% | |
| Net Assets | $ 3,518,380,158 | |
| Holdings Count | Holding | 128 | |
| Investment Company Portfolio Turnover | 17% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 3,518,380,158 Portfolio Turnover Rate (%): 17 Total Number of Holdings: 128 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 8/31/24) Portfolio structure Equities 97.6 % Money Market Funds 2.4 % Equity sectors Financials 22.8 % Industrials 18.3 % Consumer Discretionary 11.4 % Real Estate 9.6 % Materials 9.4 % Energy 6.6 % Health Care 6.0 % Information Technology 5.8 % Utilities 5.5 % Consumer Staples 2.2 % Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % MFS uses the Global Industry Classification Standard (GICS ® | |
| Largest Holdings [Text Block] | Top ten holdings ACI Worldwide, Inc. 1.7 % Portland General Electric Co. 1.4 % Pacific Premier Bancorp, Inc. 1.4 % Prosperity Bancshares, Inc. 1.3 % NorthWestern Corp. 1.3 % Viper Energy, Inc. 1.2 % National Storage Affiliates Trust, REIT 1.2 % Air Lease Corp. 1.2 % UMB Financial Corp. 1.1 % Columbia Banking System, Inc. 1.1 % | |
| C000033358 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class A | |
| Trading Symbol | DIFAX | |
| 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 (annualized) ~ A $ 0.89 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 47 | [1] |
| Expense Ratio, Percent | 0.89% | [1] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000033359 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class C | |
| Trading Symbol | DIFCX | |
| 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 (annualized) ~ C $ 1.64 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 86 | [2] |
| Expense Ratio, Percent | 1.64% | [2] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000033360 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class I | |
| Trading Symbol | DIFIX | |
| 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 (annualized) ~ I $ 0.64 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 33 | [3] |
| Expense Ratio, Percent | 0.64% | [3] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000068409 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class R1 | |
| Trading Symbol | DIFDX | |
| 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 (annualized) ~ R1 $ 1.64 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 86 | [4] |
| Expense Ratio, Percent | 1.64% | [4] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000068410 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class R2 | |
| Trading Symbol | DIFEX | |
| 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 (annualized) ~ R2 $ 1.14 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 60 | [5] |
| Expense Ratio, Percent | 1.14% | [5] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000068411 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class R3 | |
| Trading Symbol | DIFFX | |
| 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 (annualized) ~ R3 $ 0.89 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 47 | [6] |
| Expense Ratio, Percent | 0.89% | [6] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000068412 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class R4 | |
| Trading Symbol | DIFGX | |
| 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 (annualized) ~ R4 $ 0.64 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 34 | [7] |
| Expense Ratio, Percent | 0.64% | [7] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| C000117928 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | MFS® Diversified Income Fund | |
| Class Name | Class R6 | |
| Trading Symbol | DIFHX | |
| 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 (annualized) ~ R6 $ 0.55 % ˜ Expenses are direct expenses and do not include underlying fund fees and expenses. | |
| Expenses Paid, Amount | $ 29 | [8] |
| Expense Ratio, Percent | 0.55% | [8] |
| Net Assets | $ 2,180,656,106 | |
| Holdings Count | Holding | 1,350 | |
| Investment Company Portfolio Turnover | 23% | |
| Additional Fund Statistics [Text Block] | FUND STATISTICS AS OF 8/31/24 Net Assets ($): 2,180,656,106 Portfolio Turnover Rate (%): 23 Total Number of Holdings: 1,350 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 8/31/24) Portfolio structure Fixed Income 66.3 % Equities 30.9 % Money Market Funds 2.8 % Equity sectors Real Estate 12.5 % Consumer Staples 3.3 % Health Care 3.1 % Financials 2.9 % Energy 2.0 % Consumer Discretionary 1.5 % Information Technology 1.3 % Industrials 1.3 % Materials 1.1 % Communication Services 1.0 % Utilities 0.7 % ETFs 0.2 % Convertible Debt 0.0 % Index Options 0.0 % Equity Warrants 0.0 % Composition including fixed income credit quality AAA 1.7 % AA 1.9 % A 8.2 % BBB 11.6 % BB 15.2 % B 10.9 % CCC 3.4 % CC 0.2 % C 0.0 % D 0.1 % U.S. Governments 4.7 % Federal Agencies 8.4 % Not Rated 0.0 % Non-Fixed Income 30.9 % Money Market Funds 2.8 % MFS uses the Global Industry Classification Standard (GICS ® Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. The fund invests a portion of its assets in the MFS High Yield Pooled Portfolio. Percentages include the indirect exposure to the underlying holdings of the MFS High Yield Pooled Portfolio and not the direct exposure from investing in the MFS High Yield Pooled Portfolio itself. | |
| Credit Ratings Selection [Text Block] | Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change. | |
| [1]Expenses are direct expenses and do not include underlying fund fees and expenses.[2]Expenses are direct expenses and do not include underlying fund fees and expenses.[3]Expenses are direct expenses and do not include underlying fund fees and expenses.[4]Expenses are direct expenses and do not include underlying fund fees and expenses.[5]Expenses are direct expenses and do not include underlying fund fees and expenses.[6]Expenses are direct expenses and do not include underlying fund fees and expenses.[7]Expenses are direct expenses and do not include underlying fund fees and expenses.[8]Expenses are direct expenses and do not include underlying fund fees and expenses. | ||
| Shareholder Report, Holdings (Details) | Aug. 31, 2024 |
| C000002007 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002007 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002007 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002007 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002007 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002007 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002007 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002007 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002007 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002012 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002012 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002012 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002012 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002012 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002012 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002012 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002012 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002012 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002013 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002013 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002013 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002013 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002013 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002013 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002013 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002013 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002013 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002006 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002006 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002006 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002006 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002006 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002006 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002006 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002006 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002006 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002015 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002015 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002015 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002015 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002015 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002015 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002015 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002015 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002015 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002017 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002017 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002017 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002017 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002017 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002017 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002017 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002017 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002017 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002018 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002018 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002018 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002018 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002018 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002018 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002018 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002018 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002018 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000002008 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000002008 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000002008 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000002008 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002008 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000002008 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000002008 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000002008 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000002008 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000117927 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000117927 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000117927 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000117927 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000117927 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 7.10% |
| C000117927 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 95.30% |
| C000117927 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000117927 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 32.40% |
| C000117927 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 53.90% |
| C000100956 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100956 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100956 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100956 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100956 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100956 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100956 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100956 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100956 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100956 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100956 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100956 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100956 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100956 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100956 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100956 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100956 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100956 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100956 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100956 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100956 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100956 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100957 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100957 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100957 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100957 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100957 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100957 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100957 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100957 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100957 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100957 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100957 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100957 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100957 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100957 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100957 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100957 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100957 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100957 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100957 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100957 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100957 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100957 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100958 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100958 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100958 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100958 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100958 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100958 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100958 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100958 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100958 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100958 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100958 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100958 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100958 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100958 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100958 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100958 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100958 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100958 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100958 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100958 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100958 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100958 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100959 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100959 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100959 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100959 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100959 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100959 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100959 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100959 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100959 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100959 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100959 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100959 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100959 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100959 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100959 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100959 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100959 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100959 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100959 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100959 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100959 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100959 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100960 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100960 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100960 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100960 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100960 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100960 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100960 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100960 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100960 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100960 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100960 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100960 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100960 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100960 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100960 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100960 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100960 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100960 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100960 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100960 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100960 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100960 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100961 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100961 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100961 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100961 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100961 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100961 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100961 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100961 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100961 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100961 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100961 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100961 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100961 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100961 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100961 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100961 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100961 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100961 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100961 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100961 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100961 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100961 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100962 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100962 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100962 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100962 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100962 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100962 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100962 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100962 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100962 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100962 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100962 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100962 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100962 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100962 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100962 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100962 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100962 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100962 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100962 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100962 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100962 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100962 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000100963 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000100963 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100963 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000100963 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100963 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000100963 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100963 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100963 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000100963 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100963 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000100963 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000100963 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000100963 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000100963 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000100963 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000100963 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000100963 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000100963 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000100963 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000100963 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000100963 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000100963 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000117930 [Member] | ACI Worldwide Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000117930 [Member] | Portland General Electric Co [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000117930 [Member] | Pacific Premier Bancorp Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.40% |
| C000117930 [Member] | Prosperity Bancshares Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000117930 [Member] | NorthWestern Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000117930 [Member] | Viper Energy Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000117930 [Member] | National Storage Affiliates Trust REIT [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000117930 [Member] | Air Lease Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.20% |
| C000117930 [Member] | UMB Financial Corp [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000117930 [Member] | Columbia Banking System Inc [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000117930 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6.60% |
| C000117930 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 22.80% |
| C000117930 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 6% |
| C000117930 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.60% |
| C000117930 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.40% |
| C000117930 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.20% |
| C000117930 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 18.30% |
| C000117930 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.80% |
| C000117930 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 9.40% |
| C000117930 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 5.50% |
| C000117930 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.40% |
| C000117930 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 97.60% |
| C000033358 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000033358 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000033358 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000033358 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000033358 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000033358 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000033358 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000033358 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033358 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000033358 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000033358 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000033358 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033358 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000033358 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000033358 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000033358 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000033358 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000033358 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000033358 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000033358 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000033358 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000033358 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000033358 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000033358 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000033358 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000033358 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000033358 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000033358 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000033358 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033358 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000033358 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033358 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033358 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000033359 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000033359 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000033359 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000033359 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000033359 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000033359 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000033359 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000033359 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033359 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000033359 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000033359 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000033359 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033359 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000033359 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000033359 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000033359 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000033359 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000033359 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000033359 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000033359 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000033359 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000033359 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000033359 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000033359 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000033359 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000033359 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000033359 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000033359 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000033359 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033359 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000033359 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033359 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033359 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000033360 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000033360 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000033360 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000033360 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000033360 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000033360 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000033360 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000033360 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033360 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000033360 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000033360 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000033360 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033360 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000033360 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000033360 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000033360 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000033360 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000033360 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000033360 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000033360 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000033360 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000033360 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000033360 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000033360 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000033360 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000033360 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000033360 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000033360 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000033360 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033360 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000033360 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033360 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000033360 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068409 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000068409 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000068409 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000068409 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000068409 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000068409 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000068409 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068409 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068409 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000068409 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068409 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000068409 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068409 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000068409 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000068409 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000068409 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000068409 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000068409 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000068409 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068409 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068409 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000068409 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000068409 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000068409 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000068409 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068409 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000068409 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000068409 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068409 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068409 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068409 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068409 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068409 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068410 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000068410 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000068410 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000068410 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000068410 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000068410 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000068410 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068410 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068410 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000068410 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068410 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000068410 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068410 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000068410 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000068410 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000068410 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000068410 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000068410 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000068410 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068410 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068410 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000068410 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000068410 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000068410 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000068410 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068410 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000068410 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000068410 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068410 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068410 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068410 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068410 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068410 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068411 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000068411 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000068411 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000068411 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000068411 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000068411 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000068411 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068411 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068411 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000068411 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068411 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000068411 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068411 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000068411 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000068411 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000068411 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000068411 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000068411 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000068411 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068411 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068411 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000068411 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000068411 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000068411 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000068411 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068411 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000068411 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000068411 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068411 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068411 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068411 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068411 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068411 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068412 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000068412 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000068412 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000068412 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000068412 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000068412 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000068412 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068412 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068412 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000068412 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068412 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000068412 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068412 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000068412 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000068412 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000068412 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000068412 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000068412 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000068412 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068412 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000068412 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000068412 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000068412 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000068412 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000068412 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000068412 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000068412 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000068412 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000068412 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068412 [Member] | Exchange Traded Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000068412 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068412 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000068412 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000117928 [Member] | Fitch, AA Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.90% |
| C000117928 [Member] | Fitch, A Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.20% |
| C000117928 [Member] | Fitch, BBB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 11.60% |
| C000117928 [Member] | Fitch, BB Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 15.20% |
| C000117928 [Member] | Fitch, B Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 10.90% |
| C000117928 [Member] | Fitch, CCC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.40% |
| C000117928 [Member] | Fitch, CC Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000117928 [Member] | Fitch, C Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000117928 [Member] | Fitch, D Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.10% |
| C000117928 [Member] | Money Market Funds Quality [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000117928 [Member] | Moody's, Aaa Rating [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.70% |
| C000117928 [Member] | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000117928 [Member] | Energy Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2% |
| C000117928 [Member] | Financial Services Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.90% |
| C000117928 [Member] | Healthcare Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.10% |
| C000117928 [Member] | Real Estate Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 12.50% |
| C000117928 [Member] | Consumer Discretionary Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.50% |
| C000117928 [Member] | Consumer Staples Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 3.30% |
| C000117928 [Member] | Industrial Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000117928 [Member] | Information Technology Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.30% |
| C000117928 [Member] | Materials Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1.10% |
| C000117928 [Member] | Utilities Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.70% |
| C000117928 [Member] | Communications Sector [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 1% |
| C000117928 [Member] | Fixed Income Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 66.30% |
| C000117928 [Member] | Money Market Funds [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 2.80% |
| C000117928 [Member] | US Government Debt Securities [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 4.70% |
| C000117928 [Member] | Federal Agencies [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 8.40% |
| C000117928 [Member] | Equity [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
| C000117928 [Member] | Convertible Debt [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000117928 [Member] | ETFs [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0.20% |
| C000117928 [Member] | Index Options [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000117928 [Member] | Equity Warrants [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 0% |
| C000117928 [Member] | Non Fixed Income [Member] | |
| Holdings [Line Items] | |
| Percent of Total Investments | 30.90% |
