Performance Management - MFS Lifetime 2070 Fund	Apr. 30, 2026
Prospectus [Line Items]
Bar Chart and Performance Table [Heading]	Performance Information
Performance Narrative [Text Block]	The bar chart and performance table are not included because the fund has not had a full calendar year of operations. Once the fund has commenced operations, updated performance information will be available online at mfs.com or by calling 1-800-225-2606. Past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.
Performance Availability Website Address [Text]	mfs.com
Performance Availability Phone [Text]	1-800-225-2606

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