Document and Entity Information	Total
Risk/Return:
Document Type	497
Document Period End Date	Oct. 31, 2018
Registrant Name	DELAWARE GROUP ADVISER FUNDS
Central Index Key	0000910682
Amendment Flag	false
Document Creation Date	Mar. 04, 2019
Document Effective Date	Mar. 04, 2019
Prospectus Date	Mar. 04, 2019
Entity Inv Company Type	N-1A
Delaware Global Real Estate Opportunities Fund \| Class A
Risk/Return:
Trading Symbol	DGRPX
Delaware Global Real Estate Opportunities Fund \| Class C
Risk/Return:
Trading Symbol	DLPCX
Delaware Global Real Estate Opportunities Fund \| Class R
Risk/Return:
Trading Symbol	DLPRX
Delaware Global Real Estate Opportunities Fund \| Institutional Class
Risk/Return:
Trading Symbol	DGROX

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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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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'.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The date of the prospectus.

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