Condensed Financial Information of Registrant (Parent Only) Balance Sheets (Parenthetical) (Detail) - $ / shares	Dec. 31, 2024	Dec. 31, 2023
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, par value	$ 0	$ 0
Ordinary shares, shares authorized	900,000,000	900,000,000
Global Indemnity Group LLC \| Parent Company
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, par value	$ 0	$ 0
Ordinary shares, shares authorized	900,000,000	900,000,000
Class A Common Shares
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, shares issued	11,202,355	11,042,670
Ordinary shares, shares outstanding	9,914,587	9,771,429
Treasury shares, shares	1,287,768	1,271,241
Class A Common Shares \| Global Indemnity Group LLC \| Parent Company
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, shares issued	11,202,355	11,042,670
Ordinary shares, shares outstanding	9,914,587	9,771,429
Treasury shares, shares	1,287,768	1,271,241
Class B Common Shares
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, shares issued	3,793,612	3,793,612
Ordinary shares, shares outstanding	3,793,612	3,793,612
Class B Common Shares \| Global Indemnity Group LLC \| Parent Company
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, shares issued	3,793,612	3,793,612
Ordinary shares, shares outstanding	3,793,612	3,793,612
Series A Cumulative Fixed Rate Preferred Shares
Condensed Financial Statements, Captions [Line Items]
Preferred shares, par value	$ 1,000	$ 1,000
Preferred shares, shares authorized	100,000,000	100,000,000
Preferred shares, shares issued	4,000	4,000
Preferred shares, shares outstanding	4,000	4,000
Preferred shares, liquidation preference	$ 1,000	$ 1,000
Series A Cumulative Fixed Rate Preferred Shares \| Global Indemnity Group LLC \| Parent Company
Condensed Financial Statements, Captions [Line Items]
Preferred shares, par value	$ 1,000	$ 1,000
Preferred shares, shares authorized	100,000,000	100,000,000
Preferred shares, shares issued	4,000	4,000
Preferred shares, shares outstanding	4,000	4,000
Preferred shares, liquidation preference	$ 1,000	$ 1,000

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.

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