Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Feb. 28, 2023	Jun. 30, 2022
Document Information Line Items
Entity Registrant Name	NI HOLDINGS, INC.
Trading Symbol	NODK
Document Type	10-K
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		21,070,141
Entity Public Float			$ 160
Amendment Flag	false
Entity Central Index Key	0001681206
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Well-known Seasoned Issuer	No
Document Period End Date	Dec. 31, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
ICFR Auditor Attestation Flag	true
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-37973
Entity Incorporation, State or Country Code	ND
Entity Tax Identification Number	81-2683619
Entity Address, Address Line One	1101 First Avenue North
Entity Address, City or Town	Fargo
Entity Address, State or Province	ND
Entity Address, Postal Zip Code	58102
City Area Code	701
Local Phone Number	298-4200
Title of 12(b) Security	Common Stock, $0.01 par value per share
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes
Auditor Name	Mazars USA LLP
Auditor Location	Fort Washington, Pennsylvania
Auditor Firm ID	339