v3.25.1

Cover	May 15, 2025
Document Type	8-K
Amendment Flag	false
Document Period End Date	May 15, 2025
Current Fiscal Year End Date	--12-31
Entity File Number	811-21529
Entity Registrant Name	The Gabelli Global Utility & Income Trust
Entity Central Index Key	0001282957
Entity Tax Identification Number	32-0116828
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	One Corporate Center
Entity Address, City or Town	Rye
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10580-1422
City Area Code	800
Local Phone Number	422-3554
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Common Shares of Beneficial Interest
Title of 12(b) Security	Common Shares of Beneficial Interest
Trading Symbol	GLU
Security Exchange Name	NYSEAMER
Series A Cumulative Puttable and Callable Preferred Shares
Title of 12(b) Security	Series A Cumulative Puttable and Callable Preferred Shares
Trading Symbol	GLU Pr A
Security Exchange Name	NYSEAMER
Series B Cumulative Puttable and Callable Preferred Shares
Title of 12(b) Security	Series B Cumulative Puttable and Callable Preferred Shares
Trading Symbol	GLU Pr B
Security Exchange Name	NYSEAMER

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Area code of city

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End date of current fiscal year in the format --MM-DD.

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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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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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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Code for the postal or zip code

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Name of the state or province.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Indicate if registrant meets the emerging growth company criteria.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Two-character EDGAR code representing the state or country of incorporation.

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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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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Title of a 12(b) registered security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name of the Exchange on which a security is registered.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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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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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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GABELLI GLOBAL UTILITY & INCOME TRUST 8-K