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  &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border:solid black 1.0pt;border-bottom:solid black 1.5pt;   padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;TICKER   SYMBOL&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   A&lt;/font&gt;&lt;/b&gt;&lt;/p&gt; 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  &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWBX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   C&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWCX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   I&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWIX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   R1&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWGX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   R2&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MGBRX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   R3&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWHX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   R4&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWJX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt;  &lt;tr&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:none;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.3pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;Class   R5&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;   &lt;/td&gt;   &lt;td width="384" style=&apos;width:4.0in;border-top:none;border-left:solid black 1.0pt;   border-bottom:solid black 1.5pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in&apos;&gt;   &lt;p class="MsoNormal" style="font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-top:0in;margin-right:.5pt;margin-bottom:   0in;margin-left:9.5pt;margin-bottom:.0001pt;line-height:normal;text-autospace:   none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;MFWLX&lt;/font&gt;&lt;/p&gt;   &lt;/td&gt;  &lt;/tr&gt; &lt;/table&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:12.0pt;font-family:"Times New Roman","serif"&apos;&gt;&amp;nbsp;&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;The sub-sections entitled &#8220;Fees and Expenses&#8221; and &#8220;Example&#8221; beneath the main heading &amp;quot;Summary of Key Information&amp;quot; are restated in their entirety as follows:&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;margin-bottom:10.0pt;line-height:115%;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;"&gt;&amp;nbsp;&lt;/p&gt;</ck0000863032:SupplementTextBlock>
  <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="CTXT_P0001S000002469member_S000002469member">2014-02-28  &amp;nbsp;</rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
  <rr:ExpenseBreakpointDiscounts contextRef="CTXT_P0001S000002469member_S000002469member">You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds.</rr:ExpenseBreakpointDiscounts>
  <rr:ExpenseHeading contextRef="CTXT_P0001S000002469member_S000002469member">Fees and Expenses  &amp;nbsp;</rr:ExpenseHeading>
  <rr:ExpenseBreakpointMinimumInvestmentRequiredAmount contextRef="CTXT_P0001S000002469member_S000002469member" unitRef="USD" decimals="0">50000</rr:ExpenseBreakpointMinimumInvestmentRequiredAmount>
  <rr:ExpenseNarrativeTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;This table describes the fees and expenses that you may pay when you buy and hold shares of the fund. The annual fund operating expenses for Class R5 shares are based on estimated &amp;quot;Other Expenses&amp;quot; for the current fiscal year expressed as a percentage of the fund&apos;s estimated average net assets during the period.&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;text-align: justify;line-height:normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt; font-family:"Times New Roman","serif"&apos;&gt;&amp;nbsp;&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. More information about these and other waivers and reductions is available from your financial intermediary and in &#8220;Sales Charges and Waivers or Reductions&#8221; on page 9 of the fund&#8217;s prospectus and &#8220;Waivers of Sales Charges&#8221; on page I-14 of the fund&#8217;s statement of additional information Part I.&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;margin-bottom:10.0pt;line-height:115%;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;"&gt;&amp;nbsp;&lt;/p&gt;</rr:ExpenseNarrativeTextBlock>
  <rr:ShareholderFeesCaption contextRef="CTXT_P0001S000002469member_S000002469member">Shareholder Fees (fees paid directly from your investment):  &amp;nbsp;</rr:ShareholderFeesCaption>
  <rr:OperatingExpensesCaption contextRef="CTXT_P0001S000002469member_S000002469member">Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):  &amp;nbsp;</rr:OperatingExpensesCaption>
  <rr:OtherExpensesNewFundBasedOnEstimates contextRef="CTXT_P0001S000002469member_S000002469member">The annual fund operating expenses for Class R5 shares are based on estimated &amp;quot;Other Expenses&amp;quot; for the current fiscal year expressed as a percentage of the fund&apos;s estimated average net assets during the period.</rr:OtherExpensesNewFundBasedOnEstimates>
  <rr:ExpenseExampleHeading contextRef="CTXT_P0001S000002469member_S000002469member">Example</rr:ExpenseExampleHeading>
  <rr:ExpenseExampleNarrativeTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;text-align: justify;line-height:normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt; font-family:"Times New Roman","serif"&apos;&gt;&amp;nbsp;&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;The example assumes that: you invest $10,000 in the fund for the time periods indicated and you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund&#8217;s operating expenses remain the same.&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;margin-bottom:10.0pt;line-height:115%;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;"&gt;&amp;nbsp;&lt;/p&gt;</rr:ExpenseExampleNarrativeTextBlock>
  <rr:ExpenseExampleByYearCaption contextRef="CTXT_P0001S000002469member_S000002469member">Although your actual costs will likely be higher or lower, under these assumptions your costs would be:  &amp;nbsp;</rr:ExpenseExampleByYearCaption>
  <ck0000863032:Barchartandperformancetablesubheading contextRef="CTXT_P0001S000002469member_S000002469member">&lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;b&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;The paragraph that follows the Class A Bar Chart, and the Performance Table beneath the sub-section entitled &amp;quot;Performance Information&amp;quot; beneath the main heading &amp;quot;Summary of Key Information&amp;quot; are restated in their entirety as follows:&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;margin-bottom:10.0pt;line-height:115%;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;"&gt;&amp;nbsp;&lt;/p&gt;</ck0000863032:Barchartandperformancetablesubheading>
  <rr:IndexNoDeductionForFeesExpensesTaxes contextRef="CTXT_P0001S000002469member_S000002469member">Reflects no deduction for fees, expenses or taxes</rr:IndexNoDeductionForFeesExpensesTaxes>
  <rr:BarChartClosingTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;margin-bottom:0in;margin-bottom:.0001pt;line-height: normal;text-autospace:none"&gt;&lt;font style=&apos;font-size:10.0pt;font-family:"Times New Roman","serif"&apos;&gt;The total return for the three-month period ended March 31, 2012 was 6.51%. During the period(s) shown in the bar chart, the highest quarterly return was 12.25% (for the calendar quarter ended June 30, 2009) and the lowest quarterly return was (9.94)% (for the calendar quarter ended March 31, 2009).&lt;/font&gt;&lt;/p&gt;  &lt;p class="MsoNormal" style="margin-top:0in;margin-right:0in;margin-left:0in;margin-bottom:10.0pt;line-height:115%;font-size:11.0pt;font-family:&apos;calibri&apos;,&apos;sans-serif&apos;;"&gt;&amp;nbsp;&lt;/p&gt;</rr:BarChartClosingTextBlock>
  <rr:PerformanceTableHeading contextRef="CTXT_P0001S000002469member_S000002469member">Performance Table.  &amp;nbsp;</rr:PerformanceTableHeading>
  <rr:AverageAnnualReturnCaption contextRef="CTXT_P0001S000002469member_S000002469member">Average Annual Total Returns (for the Periods Ended December 31, 2011)  &amp;nbsp;</rr:AverageAnnualReturnCaption>
  <dei:TradingSymbol contextRef="S000002469member_C000006625member">MFWTX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006627member">MFWBX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000111486member">MFWLX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006628member">MFWCX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006629member">MFWIX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006631member">MFWGX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006633member">MGBRX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006634member">MFWHX</dei:TradingSymbol>
  <dei:TradingSymbol contextRef="S000002469member_C000006626member">MFWJX</dei:TradingSymbol>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006625member">A</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006627member">B</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006628member">C</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006629member">I</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006631member">ALL R</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006633member">ALL R</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006634member">ALL R</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000006626member">ALL R</rr:ShareholderFeesColumnName>
  <rr:ShareholderFeesColumnName contextRef="S000002469member_C000111486member">ALL R</rr:ShareholderFeesColumnName>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0575</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006625member" id="id_footnote_1000" unitRef="Ratio" decimals="4">0.0100</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0400</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0100</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0000</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:ShareholderFeesTableTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;div&gt; &amp;lt;div style="display:none;" &amp;gt;~ http://www.mfs.com/20120530/role/ShareholderFeesData_P0001-S000002469Member row primary compact * row dei_LegalEntityAxis compact ck0000863032_S000002469Member column rr_ProspectusShareClassAxis compact * column dei_LegalEntityAxis compact ck0000863032_S000002469Member ~&amp;lt;/div&amp;gt; &lt;/div&gt;</rr:ShareholderFeesTableTextBlock>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006625member">A</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006627member">B</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006628member">C</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006629member">I</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006631member">R1</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006633member">R2</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006634member">R3</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000006626member">R4</rr:OperatingExpensesColumnName>
  <rr:OperatingExpensesColumnName contextRef="S000002469member_C000111486member">R5</rr:OperatingExpensesColumnName>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0084</rr:ManagementFeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0025</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0100</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0100</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0000</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0100</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0050</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0025</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0000</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0000</rr:DistributionAndService12b1FeesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0021</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0014</rr:OtherExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0130</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0205</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0205</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0105</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0205</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0155</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0130</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0105</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0098</rr:ExpensesOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006625member" id="id_footnote_1001" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006627member" id="id_footnote_1002" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006628member" id="id_footnote_1003" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006629member" id="id_footnote_1004" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006631member" id="id_footnote_1005" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006633member" id="id_footnote_1006" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006634member" id="id_footnote_1007" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000006626member" id="id_footnote_1008" unitRef="Ratio" decimals="4">-0.0005</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:FeeWaiverOrReimbursementOverAssets contextRef="S000002469member_C000111486member" id="id_footnote_1009" unitRef="Ratio" decimals="4">-0.0004</rr:FeeWaiverOrReimbursementOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0125</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0200</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0200</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0100</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0200</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0150</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0125</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0100</rr:NetExpensesOverAssets>
  <rr:NetExpensesOverAssets contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0094</rr:NetExpensesOverAssets>
  <rr:AnnualFundOperatingExpensesTableTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;div&gt; &amp;lt;div style="display:none;" &amp;gt;~ http://www.mfs.com/20120530/role/OperatingExpensesData_P0001-S000002469Member row primary compact * row dei_LegalEntityAxis compact ck0000863032_S000002469Member column rr_ProspectusShareClassAxis compact * column dei_LegalEntityAxis compact ck0000863032_S000002469Member ~&amp;lt;/div&amp;gt; &lt;/div&gt;</rr:AnnualFundOperatingExpensesTableTextBlock>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006625member">Class A Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006625member" unitRef="USD" decimals="0">695</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006625member" unitRef="USD" decimals="0">955</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006625member" unitRef="USD" decimals="0">1239</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006625member" unitRef="USD" decimals="0">2045</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006627member">Class B Shares assuming redemption at end of period</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">603</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">934</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">1295</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">2180</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006628member">Class C Shares assuming redemption at end of period</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">303</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">634</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">1095</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">2372</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006629member">Class I Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006629member" unitRef="USD" decimals="0">102</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006629member" unitRef="USD" decimals="0">325</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006629member" unitRef="USD" decimals="0">571</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006629member" unitRef="USD" decimals="0">1274</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006631member">Class R1 Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006631member" unitRef="USD" decimals="0">203</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006631member" unitRef="USD" decimals="0">634</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006631member" unitRef="USD" decimals="0">1095</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006631member" unitRef="USD" decimals="0">2372</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006633member">Class R2 Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006633member" unitRef="USD" decimals="0">153</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006633member" unitRef="USD" decimals="0">481</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006633member" unitRef="USD" decimals="0">836</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006633member" unitRef="USD" decimals="0">1838</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006634member">Class R3 Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006634member" unitRef="USD" decimals="0">127</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006634member" unitRef="USD" decimals="0">403</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006634member" unitRef="USD" decimals="0">704</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006634member" unitRef="USD" decimals="0">1560</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000006626member">Class R4 Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000006626member" unitRef="USD" decimals="0">102</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000006626member" unitRef="USD" decimals="0">325</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000006626member" unitRef="USD" decimals="0">571</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000006626member" unitRef="USD" decimals="0">1274</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleByYearColumnName contextRef="S000002469member_C000111486member">Class R5 Shares</rr:ExpenseExampleByYearColumnName>
  <rr:ExpenseExampleYear01 contextRef="S000002469member_C000111486member" unitRef="USD" decimals="0">96</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 contextRef="S000002469member_C000111486member" unitRef="USD" decimals="0">305</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 contextRef="S000002469member_C000111486member" unitRef="USD" decimals="0">535</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 contextRef="S000002469member_C000111486member" unitRef="USD" decimals="0">1195</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleWithRedemptionTableTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;div&gt; &amp;lt;div style="display:none;" &amp;gt;~ http://www.mfs.com/20120530/role/ExpenseExample_P0001-S000002469Member row primary compact * row dei_LegalEntityAxis compact ck0000863032_S000002469Member column rr_ProspectusShareClassAxis compact * column dei_LegalEntityAxis compact ck0000863032_S000002469Member ~&amp;lt;/div&amp;gt; &lt;/div&gt;</rr:ExpenseExampleWithRedemptionTableTextBlock>
  <rr:ExpenseExampleNoRedemptionByYearColumnName contextRef="S000002469member_C000006627member">Class B Shares assuming  no redemption at end of period</rr:ExpenseExampleNoRedemptionByYearColumnName>
  <rr:ExpenseExampleNoRedemptionYear01 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">203</rr:ExpenseExampleNoRedemptionYear01>
  <rr:ExpenseExampleNoRedemptionYear03 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">634</rr:ExpenseExampleNoRedemptionYear03>
  <rr:ExpenseExampleNoRedemptionYear05 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">1095</rr:ExpenseExampleNoRedemptionYear05>
  <rr:ExpenseExampleNoRedemptionYear10 contextRef="S000002469member_C000006627member" unitRef="USD" decimals="0">2180</rr:ExpenseExampleNoRedemptionYear10>
  <rr:ExpenseExampleNoRedemptionByYearColumnName contextRef="S000002469member_C000006628member">Class C Shares assuming no redemption at end of period</rr:ExpenseExampleNoRedemptionByYearColumnName>
  <rr:ExpenseExampleNoRedemptionYear01 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">203</rr:ExpenseExampleNoRedemptionYear01>
  <rr:ExpenseExampleNoRedemptionYear03 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">634</rr:ExpenseExampleNoRedemptionYear03>
  <rr:ExpenseExampleNoRedemptionYear05 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">1095</rr:ExpenseExampleNoRedemptionYear05>
  <rr:ExpenseExampleNoRedemptionYear10 contextRef="S000002469member_C000006628member" unitRef="USD" decimals="0">2372</rr:ExpenseExampleNoRedemptionYear10>
  <rr:ExpenseExampleNoRedemptionTableTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;div&gt; &amp;lt;div style="display:none;" &amp;gt;~ http://www.mfs.com/20120530/role/ExpenseExampleNoRedemption_P0001-S000002469Member row primary compact * row dei_LegalEntityAxis compact ck0000863032_S000002469Member column rr_ProspectusShareClassAxis compact * column dei_LegalEntityAxis compact ck0000863032_S000002469Member ~&amp;lt;/div&amp;gt; &lt;/div&gt;</rr:ExpenseExampleNoRedemptionTableTextBlock>
  <rr:YearToDateReturnLabel contextRef="S000002469member_C000006625member">The total return for the three-month period ended</rr:YearToDateReturnLabel>
  <rr:LowestQuarterlyReturnLabel contextRef="S000002469member_C000006625member">lowest quarterly return</rr:LowestQuarterlyReturnLabel>
  <rr:HighestQuarterlyReturnLabel contextRef="S000002469member_C000006625member">highest quarterly return</rr:HighestQuarterlyReturnLabel>
  <rr:BarChartYearToDateReturnDate contextRef="S000002469member_C000006625member">2012-03-31</rr:BarChartYearToDateReturnDate>
  <rr:BarChartYearToDateReturn contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0651</rr:BarChartYearToDateReturn>
  <rr:BarChartLowestQuarterlyReturnDate contextRef="S000002469member_C000006625member">2009-03-31</rr:BarChartLowestQuarterlyReturnDate>
  <rr:BarChartLowestQuarterlyReturn contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">-0.0994</rr:BarChartLowestQuarterlyReturn>
  <rr:BarChartHighestQuarterlyReturnDate contextRef="S000002469member_C000006625member">2009-06-30</rr:BarChartHighestQuarterlyReturnDate>
  <rr:BarChartHighestQuarterlyReturn contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.1225</rr:BarChartHighestQuarterlyReturn>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006627member">B Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">-0.0246</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0186</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006627member" unitRef="Ratio" decimals="4">0.0651</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006628member">C Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0056</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0221</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006628member" unitRef="Ratio" decimals="4">0.0637</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006629member">I Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0249</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0324</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006629member" unitRef="Ratio" decimals="4">0.0743</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006631member">R1 Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0157</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0218</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006631member" unitRef="Ratio" decimals="4">0.0626</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006633member">R2 Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0205</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0270</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006633member" unitRef="Ratio" decimals="4">0.0676</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006634member">R3 Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0230</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0295</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006634member" unitRef="Ratio" decimals="4">0.0707</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006626member">R4 Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0255</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0320</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006626member" unitRef="Ratio" decimals="4">0.0737</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000111486member">R5 Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0249</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0324</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000111486member" unitRef="Ratio" decimals="4">0.0743</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006625member">A Shares Returns Before Taxes</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">-0.0367</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0172</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006625member" unitRef="Ratio" decimals="4">0.0645</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006625member_Aftertaxesondistributionsmember">A Shares Returns After Taxes on Distributions</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006625member_Aftertaxesondistributionsmember" unitRef="Ratio" decimals="4">-0.0425</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006625member_Aftertaxesondistributionsmember" unitRef="Ratio" decimals="4">0.0070</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006625member_Aftertaxesondistributionsmember" unitRef="Ratio" decimals="4">0.0519</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_C000006625member_Aftertaxesondistributionsandsalesmember">A Shares Returns After Taxes on Distributions and Sale of Fund Shares</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_C000006625member_Aftertaxesondistributionsandsalesmember" unitRef="Ratio" decimals="4">-0.0204</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_C000006625member_Aftertaxesondistributionsandsalesmember" unitRef="Ratio" decimals="4">0.0109</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_C000006625member_Aftertaxesondistributionsandsalesmember" unitRef="Ratio" decimals="4">0.0515</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmsciworldindexgrossdivmember">Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI World Index (gross div)</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmsciworldindexgrossdivmember" unitRef="Ratio" decimals="4">-0.0502</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmsciworldindexgrossdivmember" unitRef="Ratio" decimals="4">-0.0182</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmsciworldindexgrossdivmember" unitRef="Ratio" decimals="4">0.0415</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesbarclayscapitalglobalaggregatebondindexmember">Index Comparisons (Reflects no deduction for fees, expenses or taxes) Barclays Capital Global Aggregate Bond Index</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesbarclayscapitalglobalaggregatebondindexmember" unitRef="Ratio" decimals="4">0.0564</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesbarclayscapitalglobalaggregatebondindexmember" unitRef="Ratio" decimals="4">0.0646</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesbarclayscapitalglobalaggregatebondindexmember" unitRef="Ratio" decimals="4">0.0716</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnLabel contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmfsglobaltotalreturnblendedindexgrossdivmember" id="id_footnote_1010">Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Global Total Return Blended Index   (gross div)</rr:AverageAnnualReturnLabel>
  <rr:AverageAnnualReturnYear01 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmfsglobaltotalreturnblendedindexgrossdivmember" unitRef="Ratio" decimals="4">-0.0062</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmfsglobaltotalreturnblendedindexgrossdivmember" unitRef="Ratio" decimals="4">0.0184</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 contextRef="S000002469member_I000Indexcomparisonsreflectsnodeductionforfeesexpensesortaxesmfsglobaltotalreturnblendedindexgrossdivmember" unitRef="Ratio" decimals="4">0.0569</rr:AverageAnnualReturnYear10>
  <rr:PerformanceTableTextBlock contextRef="CTXT_P0001S000002469member_S000002469member">&lt;div&gt; &amp;lt;div style="display:none;" &amp;gt;~ http://www.mfs.com/20120530/role/PerformanceTableData_P0001-S000002469Member row primary compact * row dei_LegalEntityAxis compact ck0000863032_S000002469Member column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * column dei_LegalEntityAxis compact ck0000863032_S000002469Member ~&amp;lt;/div&amp;gt; &lt;/div&gt;</rr:PerformanceTableTextBlock>
  <link:footnoteLink xlink:type="extended" xlink:role="http://www.xbrl.org/2003/role/link">
    <link:footnote xlink:type="resource" xlink:label="footnote_1000" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US">On shares purchased without an initial sales charge and redeemed within 24 months of purchase.</link:footnote>
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    <link:footnoteArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote" xlink:from="MaximumDeferredSalesChargeOverOfferingPrice_1001" xlink:to="footnote_1000" order="1.0" />
    <link:footnote xlink:type="resource" xlink:label="footnote_1001" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US">Massachusetts Financial Services Company has agreed in writing to reduce its management fee to 0.75% of the fund&#8217;s average daily net assets annually in excess of $500 million up to $1 billion, and 0.70% of the fund&#8217;s average daily net assets annually in excess of $1 billion. This written agreement will remain in effect until modified by the fund&#8217;s Board of Trustees, but such agreement will continue until at least February 28, 2014. In addition, Massachusetts Financial Services Company has agreed in writing to bear the fund&#8217;s expenses, excluding interest, taxes, extraordinary expenses, brokerage and transaction costs and investment-related expenses (such as interest and borrowing expenses incurred in connection with the fund&#8217;s investment activity), such that &#8220;Total Annual Fund Operating Expenses&#8221; do not exceed 1.25% of the fund&#8217;s average daily net assets annually for each of Class A and Class R3 shares, 2.00% of the fund&#8217;s average daily net assets annually for each of Class B, Class C and Class R1 shares, 1.00% of the fund&#8217;s average daily net assets annually for each of Class I and Class R4 shares, 1.50% of the fund&#8217;s average daily net assets annually for Class R2 shares, and 0.94% of the fund&#8217;s average daily net assets annually for Class R5 shares. This written agreement will continue until modified by the fund&#8217;s Board of Trustees, but such agreement will continue until at least February 28, 2014.</link:footnote>
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    <link:loc xlink:type="locator" xlink:href="#id_footnote_1007" xlink:label="FeeWaiverOrReimbursementOverAssets_1008" />
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    <link:footnote xlink:type="resource" xlink:label="footnote_1002" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US">The MFS Global Total Return Blended Index (gross div) was composed at period end of the following amounts of the following indices: 60% MSCI World Index (gross div) and 40% Barclays Capital Global Aggregate Bond Index.</link:footnote>
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