Document and Entity Information
Feb. 24, 2020
Cover [Abstract]  
Amendment Flag false
Entity Central Index Key 0001561660
Document Type 8-K
Document Period End Date Feb. 24, 2020
Entity Registrant Name PATTERN ENERGY GROUP INC.
Entity Incorporation, State or Country Code DE
Entity File Number 001-36087
Entity Tax Identification Number 90-0893251
Entity Address, Address Line One 1088 Sansome Street
Entity Address, City or Town San Francisco
Entity Address, State or Province CA
Entity Address, Postal Zip Code 94111
City Area Code 415
Local Phone Number 283-4000
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Class A common stock
Trading Symbol PEGI
Security Exchange Name NASDAQ
Entity Emerging Growth Company false