Document and Entity Information	0 Months Ended
Aug. 28, 2013
Risk/Return:
Document Type	497
Document Period End Date	Aug. 28, 2013
Registrant Name	MFS SERIES TRUST XVI
Central Index Key	0000063067
Amendment Flag	false
Document Creation Date	Aug. 28, 2013
Document Effective Date	Aug. 28, 2013
Prospectus Date	Oct. 28, 2012
MFS® Global Multi-Asset Fund \| A
Risk/Return:
Trading Symbol	GLMAX
MFS® Global Multi-Asset Fund \| B
Risk/Return:
Trading Symbol	GLMBX
MFS® Global Multi-Asset Fund \| C
Risk/Return:
Trading Symbol	GLMCX
MFS® Global Multi-Asset Fund \| I
Risk/Return:
Trading Symbol	GLMIX
MFS® Global Multi-Asset Fund \| R1
Risk/Return:
Trading Symbol	GLMRX
MFS® Global Multi-Asset Fund \| R2
Risk/Return:
Trading Symbol	GLMSX
MFS® Global Multi-Asset Fund \| R3
Risk/Return:
Trading Symbol	GLMTX
MFS® Global Multi-Asset Fund \| R4
Risk/Return:
Trading Symbol	GLMUX
MFS® Global Multi-Asset Fund \| R5
Risk/Return:
Trading Symbol	GLMVX

If the value is true, then the document is an amendment to previously-filed/accepted document.

No definition available.

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- Definition

The date the document was made available and submitted, in CCYY-MM-DD format. The date of submission, date of acceptance by the recipient, and the document effective date are all potentially different.

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No definition available.

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The date when a document, upon receipt and acceptance, becomes officially effective, in CCYY-MM-DD format. Usually it is a system-assigned date time value, but it may be declared by the submitter in some cases.

+ References

No definition available.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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No definition available.

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- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other".

+ References

No definition available.

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation 12B

-Number 240

-Section 12b

-Subsection 1

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Trading symbol of an instrument as listed on an exchange.

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- Definition

The date of the prospectus.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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