Schedule of Condensed Consolidating Statements of Operations (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues:
Net premiums earned		$ 120,528	$ 108,619	$ 342,447	$ 328,818
Net investment income		11,750	10,134	34,108	27,618
Net realized investment gains (losses)		5,319	(963)	7,833	(850)
Other income (loss)		411	2,294	1,289	5,444
Total revenues		138,008	120,084	385,677	361,030
Losses and Expenses:
Net losses and loss adjustment expenses		80,493	82,395	195,426	202,656
Acquisition costs and other underwriting expenses		48,680	45,002	141,196	135,010
Corporate and other operating expenses		3,475	4,630	23,653	11,045
Interest expense		4,924	4,836	14,725	12,065
Income (loss) before income taxes		436	(16,779)	10,677	254
Income (loss) before income taxes		436	(16,779)	10,677	254
Income tax benefit		(3,292)	(7,855)	(5,944)	(13,193)
Net income (loss)		3,728	(8,924)	16,621	13,447
Global Indemnity Limited (Parent co-obligor)
Revenues:
Net investment income		146	104	483	256
Net realized investment gains (losses)		(101)	23	(121)	(226)
Total revenues		45	127	362	30
Losses and Expenses:
Corporate and other operating expenses		982	2,209	9,959	3,709
Interest expense		2,017	5,176	12,715	12,769
Income (loss) before income taxes		(2,954)	(7,258)	(22,312)	(16,448)
Equity in net income (loss) of subsidiaries		6,682	(1,666)	38,933	29,895
Income (loss) before income taxes		3,728	(8,924)	16,621	13,447
Net income (loss)		3,728	(8,924)	16,621	13,447
Global Indemnity Group, Inc.(Subsidiary co-obligor)
Revenues:
Net investment income		2,492	2,321	8,404	5,105
Net realized investment gains (losses)		5,321	(1,229)	8,167	(1,830)
Other income (loss)		(12)	1,738		3,514
Total revenues		7,801	2,830	16,571	6,789
Losses and Expenses:
Corporate and other operating expenses		2,089	(6,441)	12,734	(12,104)
Interest expense		12,035	11,237	34,773	31,087
Income (loss) before income taxes		(6,323)	(1,966)	(30,936)	(12,194)
Equity in net income (loss) of subsidiaries		(3,995)	(12,523)	6,770	(14,211)
Income (loss) before income taxes		(10,318)	(14,489)	(24,166)	(26,405)
Income tax benefit		(1,884)	(211)	(2,831)	(4,057)
Net income (loss)		(8,434)	(14,278)	(21,335)	(22,348)
Other Global Indemnity Limited Subsidiaries and Eliminations (non-co-obligor subsidiaries)
Revenues:
Net premiums earned	[1]	120,528	108,619	342,447	328,818
Net investment income	[1]	18,318	19,351	58,258	54,316
Net realized investment gains (losses)	[1]	99	243	(213)	1,206
Other income (loss)	[1]	423	556	1,289	1,930
Total revenues	[1]	139,368	128,769	401,781	386,270
Losses and Expenses:
Net losses and loss adjustment expenses	[1]	80,493	82,395	195,426	202,656
Acquisition costs and other underwriting expenses	[1]	48,680	45,002	141,196	135,010
Corporate and other operating expenses	[1]	404	8,862	960	19,440
Interest expense	[1]	78	65	274	268
Income (loss) before income taxes	[1]	9,713	(7,555)	63,925	28,896
Equity in net income (loss) of subsidiaries	[1]	(8,434)	(14,822)	(21,335)	(22,781)
Income (loss) before income taxes	[1]	1,279	(22,377)	42,590	6,115
Income tax benefit	[1]	(1,408)	(7,644)	(3,226)	(9,136)
Net income (loss)	[1]	2,687	(14,733)	45,816	15,251
Consolidation Adjustments
Revenues:
Net investment income	[2]	(9,206)	(11,642)	(33,037)	(32,059)
Total revenues	[2]	(9,206)	(11,642)	(33,037)	(32,059)
Losses and Expenses:
Interest expense	[2]	(9,206)	(11,642)	(33,037)	(32,059)
Equity in net income (loss) of subsidiaries	[2]	5,747	29,011	(24,368)	7,097
Income (loss) before income taxes	[2]	5,747	29,011	(24,368)	7,097
Income tax benefit	[2]			113
Net income (loss)	[2]	$ 5,747	$ 29,011	$ (24,481)	$ 7,097

[1] Includes all other subsidiaries of Global Indemnity Limited and eliminations

[2] Includes Parent co-obligor and subsidiary co-obligor consolidating adjustments