NORTHWESTERN CORP

Q: Sep 30 2023

Q: Jun 30 2023

Q: Mar 31 2023

FY: Dec 31 2022

Q: Sep 30 2022

Q: Jun 30 2022

Q: Mar 31 2022

FY: Dec 31 2021

Q: Sep 30 2021

Q: Jun 30 2021

Q: Mar 31 2021

FY: Dec 31 2020

Q: Sep 30 2020

Q: Jun 30 2020

Q: Mar 31 2020

FY: Dec 31 2019

Q: Sep 30 2019

Q: Jun 30 2019

Q: Mar 31 2019

FY: Dec 31 2018

7.01,9.01

1.01,2.03

7.01,9.01

2.02,7.01,9.01

1.01,3.01,3.03,5.02,5.03,9.01

7.01,9.01

2.02,7.01,9.01

2.03,9.01

1.01,9.01

1.01,9.01

7.01,9.01

5.02,9.01

7.01,9.01

1.01,2.03,9.01

5.07

2.02,7.01,9.01

1.01,2.03,9.01

8.01,9.01

7.01,9.01

7.01,9.01

Certification of termination of registration of a class of securities (Section 12(g))

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Notification of removal from listing and/or registration on a national securities exchange

Prospectus Supplement for Primary Offering

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Prospectus Supplement for Delayed or Continuous Offering

Prospectus Supplement for Primary Offering

Automatic Shelf Registration

Prospectus Supplement for Primary Offering

Prospectus Supplement for Primary Offering

Prospectus Supplement for Primary Offering

Free Writing Prospectus

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Preliminary Proxy Statement

Additional Information for Proxy Statement/ Votes

none

none

LaFave Bleau

Ide Britt E

none

Edwards Sherina M.

Edwards Sherina M.

Hines John D

Cashell Michael R

Berzina Jeffrey B.

Fang Cynthia

Merkel Jason

Pohl Curtis T

BIRD BRIAN B

Vold Jeanne

Schroeppel Bobbi L

Lail Crystal Dawn

Heim Shannon

none

BIRD BRIAN B

Post-effective amendment to an automatic shelf registration statement

Post-effective amendment to an automatic shelf registration statement

Annual Report Scanned (Paper)

Letter from the SEC

Correspondence with the SEC

Letter from the SEC

Notification of the removal from listing and registration of matured redeemed or retired securities

Letter from the SEC

Correspondence with the SEC

Letter from the SEC

No description available

Letter from the SEC

Correspondence with the SEC

Letter from the SEC

Annual Report Scanned (Paper)

Annual Report Scanned (Paper)

Annual Report Scanned (Paper)

Letter from the SEC

Correspondence with the SEC

Letter from the SEC