Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries - Additional Information (Detail)	9 Months Ended
Sep. 30, 2019
Global Indemnity Group Inc
Condensed Financial Statements, Captions [Line Items]
Ownership percentage in subsidiary	100.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Namespace Prefix:	srt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration