Segment Information (Details) - Schedule of Revenue by Insurance Product Line - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Schedule of Revenue by Insurance Product Line [Line Items]
Direct premiums earned	$ 90,125	$ 85,600	$ 257,024	$ 238,892
Assumed premiums earned	1,880	2,045	2,684	3,448
Ceded premiums earned	(8,735)	(11,227)	(21,385)	(24,216)
Net premiums earned	83,270	76,418	238,323	218,124
Direct losses and loss adjustment expenses	69,692	53,863	184,561	162,027
Assumed losses and loss adjustment expenses	617	725	886	882
Ceded losses and loss adjustment expenses	(5,209)	(1,431)	(10,845)	(8,550)
Net losses and loss adjustment expenses	65,100	53,157	174,602	154,359
Gross margin	18,170	23,261	63,721	63,765
Underwriting and general expenses	27,340	23,853	80,381	70,917
Underwriting gain (loss)	(9,170)	(592)	(16,660)	(7,152)
Fee and other income	491	445	1,590	1,196
Net investment income	2,811	2,121	8,089	5,735
Net investment gains (losses)	2,412	(955)	3,288	275
Loss before income taxes	(3,456)	1,019	(3,693)	54
Income tax expense (benefit)	(751)	214	(445)	11
Net income (loss)	(2,705)	805	(3,248)	43
Net loss attributable to non-controlling interest		67		(336)
Net income attributable to NI Holdings, Inc.	$ (2,705)	$ 738	$ (3,248)	$ 379
Operating Ratios:
Loss and loss adjustment expense ratio	78.20%	69.60%	73.30%	70.80%
Expense ratio	32.80%	31.20%	33.70%	32.50%
Combined ratio	111.00%	100.80%	107.00%	103.30%
Premiums and agents’ balances receivable	$ 85,315	$ 87,621	$ 85,315	$ 87,621
Deferred policy acquisition costs	27,471	25,540
Reinsurance recoverables on losses	14,321	10,702	14,321	10,702	$ 6,460
Receivable from Federal Crop Insurance Corporation	19,605	14,479	19,605	14,479
Goodwill and other intangibles	2,728	2,728	2,728	2,728	2,728
Unpaid losses and loss adjustment expenses	159,069	142,448	159,069	142,448	119,185
Unearned premiums	136,880	131,088	136,880	131,088	$ 126,100
Private Passenger Auto [Member]
Schedule of Revenue by Insurance Product Line [Line Items]
Direct premiums earned	23,981	22,377	70,600	64,426
Assumed premiums earned
Ceded premiums earned	(1,369)	(1,142)	(3,415)	(2,995)
Net premiums earned	22,612	21,235	67,185	61,431
Direct losses and loss adjustment expenses	15,300	16,148	47,608	50,227
Assumed losses and loss adjustment expenses
Ceded losses and loss adjustment expenses	(1,230)	455	(2,316)	867
Net losses and loss adjustment expenses	14,070	16,603	45,292	51,094
Gross margin	8,542	4,632	21,893	10,337
Underwriting and general expenses	7,470	6,126	21,327	18,406
Underwriting gain (loss)	$ 1,072	$ (1,494)	$ 566	$ (8,069)
Operating Ratios:
Loss and loss adjustment expense ratio	62.20%	78.20%	67.40%	83.20%
Expense ratio	33.00%	28.80%	31.70%	30.00%
Combined ratio	95.20%	107.00%	99.10%	113.20%
Premiums and agents’ balances receivable	$ 26,863	$ 23,901	$ 26,863	$ 23,901
Deferred policy acquisition costs	6,636	5,744
Reinsurance recoverables on losses	2,142	139	2,142	139
Receivable from Federal Crop Insurance Corporation
Goodwill and other intangibles
Unpaid losses and loss adjustment expenses	34,777	33,124	34,777	33,124
Unearned premiums	38,309	35,059	38,309	35,059
Non-Standard Auto [Member]
Schedule of Revenue by Insurance Product Line [Line Items]
Direct premiums earned	23,069	21,334	74,947	64,049
Assumed premiums earned
Ceded premiums earned	(68)	(103)	(214)	(295)
Net premiums earned	23,001	21,231	74,733	63,754
Direct losses and loss adjustment expenses	20,504	18,838	56,687	50,015
Assumed losses and loss adjustment expenses
Ceded losses and loss adjustment expenses
Net losses and loss adjustment expenses	20,504	18,838	56,687	50,015
Gross margin	2,497	2,393	18,046	13,739
Underwriting and general expenses	10,327	8,719	30,892	26,511
Underwriting gain (loss)	(7,830)	(6,326)	(12,846)	(12,772)
Fee and other income	281	278	971	748
Total	$ (7,549)	$ (6,048)	$ (11,875)	$ (12,024)
Operating Ratios:
Loss and loss adjustment expense ratio	89.10%	88.70%	75.90%	78.50%
Expense ratio	44.90%	41.10%	41.30%	41.60%
Combined ratio	134.00%	129.80%	117.20%	120.10%
Premiums and agents’ balances receivable	$ 12,076	$ 15,854	$ 12,076	$ 15,854
Deferred policy acquisition costs	9,279	9,797
Reinsurance recoverables on losses
Receivable from Federal Crop Insurance Corporation
Goodwill and other intangibles	2,728	2,728	2,728	2,728
Unpaid losses and loss adjustment expenses	73,447	59,663	73,447	59,663
Unearned premiums	28,725	31,072	28,725	31,072
Home and Farm [Member]
Schedule of Revenue by Insurance Product Line [Line Items]
Direct premiums earned	26,092	23,650	75,336	69,077
Assumed premiums earned
Ceded premiums earned	(2,613)	(2,341)	(8,519)	(7,363)
Net premiums earned	23,479	21,309	66,817	61,714
Direct losses and loss adjustment expenses	23,248	14,611	58,604	42,548
Assumed losses and loss adjustment expenses
Ceded losses and loss adjustment expenses	(1,225)	(559)	(2,374)	(1,862)
Net losses and loss adjustment expenses	22,023	14,052	56,230	40,686
Gross margin	1,456	7,257	10,587	21,028
Underwriting and general expenses	7,618	6,207	21,561	18,672
Underwriting gain (loss)	$ (6,162)	$ 1,050	$ (10,974)	$ 2,356
Operating Ratios:
Loss and loss adjustment expense ratio	93.80%	65.90%	84.20%	65.90%
Expense ratio	32.40%	29.10%	32.30%	30.30%
Combined ratio	126.20%	95.00%	116.50%	96.20%
Premiums and agents’ balances receivable	$ 11,043	$ 9,655	$ 11,043	$ 9,655
Deferred policy acquisition costs	9,620	7,973
Reinsurance recoverables on losses	3,648	3,918	3,648	3,918
Receivable from Federal Crop Insurance Corporation
Goodwill and other intangibles
Unpaid losses and loss adjustment expenses	23,947	24,489	23,947	24,489
Unearned premiums	54,409	48,636	54,409	48,636
Crop [Member]
Schedule of Revenue by Insurance Product Line [Line Items]
Direct premiums earned	13,649	15,283	26,565	32,800
Assumed premiums earned	1,610	1,792	2,113	2,293
Ceded premiums earned	(4,374)	(7,329)	(8,363)	(12,735)
Net premiums earned	10,885	9,746	20,315	22,358
Direct losses and loss adjustment expenses	7,588	4,899	14,542	16,932
Assumed losses and loss adjustment expenses	439	558	687	558
Ceded losses and loss adjustment expenses	(1,837)	(1,767)	(3,285)	(6,363)
Net losses and loss adjustment expenses	6,190	3,690	11,944	11,127
Gross margin	4,695	6,056	8,371	11,231
Underwriting and general expenses	1,783	1,973	3,494	4,687
Underwriting gain (loss)	$ 2,912	$ 4,083	$ 4,877	$ 6,544
Operating Ratios:
Loss and loss adjustment expense ratio	56.90%	37.90%	58.80%	49.80%
Expense ratio	16.40%	20.20%	17.20%	21.00%
Combined ratio	73.30%	58.10%	76.00%	70.80%
Premiums and agents’ balances receivable	$ 32,751	$ 35,982	$ 32,751	$ 35,982
Deferred policy acquisition costs	786	1,046
Reinsurance recoverables on losses	3,532	4,676	3,532	4,676
Receivable from Federal Crop Insurance Corporation	19,605	14,479	19,605	14,479
Goodwill and other intangibles
Unpaid losses and loss adjustment expenses	16,493	16,614	16,493	16,614
Unearned premiums	8,614	10,208	8,614	10,208
All Other [Member]
Schedule of Revenue by Insurance Product Line [Line Items]
Direct premiums earned	3,334	2,956	9,576	8,540
Assumed premiums earned	270	253	571	1,155
Ceded premiums earned	(311)	(312)	(874)	(828)
Net premiums earned	3,293	2,897	9,273	8,867
Direct losses and loss adjustment expenses	3,052	(633)	7,120	2,305
Assumed losses and loss adjustment expenses	178	167	199	324
Ceded losses and loss adjustment expenses	(917)	440	(2,870)	(1,192)
Net losses and loss adjustment expenses	2,313	(26)	4,449	1,437
Gross margin	980	2,923	4,824	7,430
Underwriting and general expenses	142	828	3,107	2,641
Underwriting gain (loss)	$ 838	$ 2,095	$ 1,717	$ 4,789
Operating Ratios:
Loss and loss adjustment expense ratio	70.20%	(0.90%)	48.00%	16.20%
Expense ratio	4.30%	28.60%	33.50%	29.80%
Combined ratio	74.50%	27.70%	81.50%	46.00%
Premiums and agents’ balances receivable	$ 2,582	$ 2,229	$ 2,582	$ 2,229
Deferred policy acquisition costs	1,150	980
Reinsurance recoverables on losses	4,999	1,969	4,999	1,969
Receivable from Federal Crop Insurance Corporation
Goodwill and other intangibles
Unpaid losses and loss adjustment expenses	10,405	8,558	10,405	8,558
Unearned premiums	$ 6,823	$ 6,113	$ 6,823	$ 6,113