XML 85 R75.htm IDEA: XBRL DOCUMENT v3.23.3

Schedule of Distributions Declared (Detail) - USD ($) $ in Thousands														9 Months Ended
		Oct. 16, 2023	Sep. 28, 2023	Jun. 30, 2023	Jun. 01, 2023	Mar. 31, 2023	Mar. 02, 2023	Oct. 11, 2022	Sep. 23, 2022	Jun. 30, 2022	Jun. 02, 2022	Mar. 31, 2022	Mar. 03, 2022	Sep. 30, 2023	Sep. 30, 2022
Dividends Payable [Line Items]
Approval Date			Sep. 28, 2023		Jun. 01, 2023		Mar. 02, 2023		Sep. 23, 2022		Jun. 02, 2022		Mar. 03, 2022
Record Date			Oct. 09, 2023		Jun. 23, 2023		Mar. 24, 2023		Oct. 04, 2022		Jun. 20, 2022		Mar. 21, 2022
Payment Date			Oct. 16, 2023		Jun. 30, 2023		Mar. 31, 2023		Oct. 11, 2022		Jun. 30, 2022		Mar. 31, 2022	Oct. 16, 2023
Payment of dividends		$ 3,385		$ 3,375		$ 3,410		$ 3,616		$ 3,602		$ 3,597		$ 10,150	$ 11,089
Unvested Shares, Net of Forfeitures
Dividends Payable [Line Items]
Approval Date	[1]													Various	Various
Record Date	[1]													Various	Various
Payment Date	[1]													Various	Various
Payment of dividends	[1]													$ (20)
Payment of dividends	[1]														$ 274
[1] Represents distributions declared on unvested shares, net of forfeitures.

X

- Definition

Dividends approval date description.

+ References

No definition available.

+ Details

Name:	gbli_DividendsApprovalDateDescription
Namespace Prefix:	gbli_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Dividends net of forfeitures.

+ References

No definition available.

+ Details

Name:	gbli_DividendsNetOfForfeitures
Namespace Prefix:	gbli_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Dividends payment date description.

+ References

No definition available.

+ Details

Name:	gbli_DividendsPaymentDateDescription
Namespace Prefix:	gbli_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Dividends record date description.

+ References

No definition available.

+ Details

Name:	gbli_DividendsRecordDateDescription
Namespace Prefix:	gbli_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Date the declared dividend will be paid, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-3

+ Details

Name:	us-gaap_DividendPayableDateToBePaidDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481071/942-405-45-2

+ Details

Name:	us-gaap_Dividends
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Date the dividend to be paid was declared, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-3

+ Details

Name:	us-gaap_DividendsPayableDateDeclaredDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Date the holder must own the stock to be entitled to the dividend, in YYYY-MM-DD format.

+ References

No definition available.

+ Details

Name:	us-gaap_DividendsPayableDateOfRecordDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_DividendsPayableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_VestingAxis=gbli_UnvestedSharesNetOfForfeituresMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: