v3.19.3.a.u2
Cover Document
Jan. 30, 2020
Cover page.  
Entity Central Index Key 0000066756
Amendment Flag false
Document Type 8-K
Document Period End Date Jan. 30, 2020
Entity Registrant Name ALLETE, Inc
Entity Incorporation, State or Country Code MN
Entity File Number 1-3548
Entity Tax Identification Number 41-0418150
Entity Address, Address Line One 30 West Superior Street
Entity Address, City or Town Duluth
Entity Address, State or Province MN
Entity Address, Postal Zip Code 55802-2093
City Area Code 218
Local Phone Number 279-5000
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock, without par value
Trading Symbol ALE
Security Exchange Name NYSE
Entity Emerging Growth Company false