Maximum number of standard twenty-foot equivalent unit (TEU) shipping containers a vessel can carry.

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Number of newbuilding vessels to be purchased.

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The number of vessels delivered according to a vessel purchase agreement.

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Number of vessels owned.

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The number of vessels acquired by the company.

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Number of vessels that have been successfully sold and transferred to buyers during a reporting period.

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No definition available.

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Number of vessels that exercised extension terms as outlined in the contract.

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Number of vessels that a company plans or has agreed to dispose of during a specified period.

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No definition available.

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Number of vessels under construction as of the reporting date.

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Gross sale price of long-lived, physical assets used in the normal conduct of business.

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The period by which an existing charter agreement may be extended beyond its original expiration date, according to to the terms of charter agreement.

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No definition available.

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The contractually agreed period during which a vessel is chartered before any optional extension or renewals.

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No definition available.

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An additional buffer of time added around the expected end of a vessel charter to provide flexibility for operational and scheduling uncertainties.

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No definition available.

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The optional period by which an existing charter agreement may be extended beyond its original expiration date, according to to the terms of charter agreement after drydocking.

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The frequency of extension refers to how many times or how often a charter can be extended under the charter agreement.

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No definition available.

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The average age of containerships owned by the Company.

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Name Accounting Standards Codification
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Amount of increase in property, plant, and equipment from addition. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Description of Business (Details) $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended	12 Months Ended
Description of Business (Details) $ in Thousands	Dec. 31, 2018 Vessel	Dec. 31, 2025 USD ($) Vessel TEU	Mar. 31, 2025 Vessel	Dec. 31, 2024 USD ($) Vessel TEU	Jun. 30, 2023 USD ($) Vessel TEU	Jun. 30, 2026 USD ($) Vessel TEU Extensions	Dec. 31, 2021 Vessel TEU	Jan. 09, 2026 Vessel	Nov. 15, 2018 Vessel
Description of Business [Abstract]
Number of vessels purchased (in Vessel)							23		20
Number of vessels owned (in Vessel)						71
Weighted average age of vessels						18 years 4 months 24 days
Subsidiaries [Member]
Description of Business [Abstract]
Ownership interest in subsidiaries						100.00%
Argos [Member]
Description of Business [Abstract]
Number of vessels sold (in Vessel)	1
Seven Vessels [Member]
Description of Business [Abstract]
Number of vessels purchased (in Vessel)							7
Vessel capacity (in TEU) \| TEU							6,000
Twelve Vessels [Member]
Description of Business [Abstract]
Number of vessels purchased (in Vessel)							12
Four Vessels [Member]
Description of Business [Abstract]
Number of vessels purchased (in Vessel)							4
Vessel capacity (in TEU) \| TEU							5,470
Four New Vessels [Member]
Description of Business [Abstract]
Number of vessels purchased (in Vessel)					4
Vessel capacity (in TEU) \| TEU					8,544
Purchase price (in Dollars) \| $					$ 123,300
Zim Norfolk and Zim Xiamen [Member] \| Minimum [Member]
Description of Business [Abstract]
Vesssels charter extension term						60 months
Zim Norfolk and Zim Xiamen [Member] \| Maximum [Member]
Description of Business [Abstract]
Vesssels charter extension term						63 months
Sydney, Istanbul and Bremerhaven Express [Member]
Description of Business [Abstract]
Vessel capacity (in TEU) \| TEU						9,019
Vesssels charter extension term						12 months
Vessels firm charter term, frequency of extension (in Extensions) \| Extensions						3
Bremerhaven Express and Sydney Express [Member]
Description of Business [Abstract]
Vesssels charter extension term						12 months
Istanbul Express and Czech [Member]
Description of Business [Abstract]
Vesssels charter extension term						12 months
MSC Tianjin, MSC Qingdao, Agios Dimitrios and GSL Ningbo [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						36 months
MSC Tianjin, MSC Qingdao, Agios Dimitrios and GSL Ningbo [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						38 months
GSL Alexandra, GSL Sofia, GSL Lydia and GSL Effie [Member]
Description of Business [Abstract]
Vesssels charter extension term						1 year
Vessels charter fixed term, cushion period						30 days
Vessels charter optional extension term after drydocking						2 years
GSL Alexandra, GSL Sofia, GSL Lydia and GSL Effie [Member] \| Minimum [Member]
Description of Business [Abstract]
Vesssels charter extension term						36 months
Vessels charter fixed term						24 months
Vessels charter optional extension term after drydocking						24 months
GSL Alexandra, GSL Sofia, GSL Lydia and GSL Effie [Member] \| Maximum [Member]
Description of Business [Abstract]
Vesssels charter extension term						38 months
Vessels charter optional extension term after drydocking						26 months
GSL Eleni, GSL Kalliopi and GSL Grania [Member] \| Minimum [Member]
Description of Business [Abstract]
Vesssels charter extension term						12 months
Vessels charter fixed term						35 months
GSL Eleni, GSL Kalliopi and GSL Grania [Member] \| Maximum [Member]
Description of Business [Abstract]
Vesssels charter extension term						16 months
Vessels charter fixed term						38 months
Colombia Express, Panama Express, Costa Rica Express, Nicaragua Express, Mexico Express, Jamaica Express [Member]
Description of Business [Abstract]
Vesssels charter extension term						12 months
Vessels firm charter term, frequency of extension (in Extensions) \| Extensions						2
Ateti [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						36 months
Ateti [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						38 months
GSL Vinia and GSL Christel Elizabeth [Member]
Description of Business [Abstract]
Vesssels charter extension term						12 months
GSL Vinia and GSL Christel Elizabeth [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						36 months
GSL Vinia and GSL Christel Elizabeth [Member] \| Maximum [Member]
Description of Business [Abstract]
Vesssels charter extension term						15 months
Vessels charter fixed term						40 months
GSL Maria, GSL Violetta, GSL Arcadia, GSL MYNY, GSL Melita, GSL Tegea and GSL Dorothea [Member]
Description of Business [Abstract]
Vesssels charter extension term						12 months
Number of vessels that exercised extension terms (in Vessel)						7
GSL Maria, GSL Violetta, GSL Arcadia, GSL MYNY, GSL Melita, GSL Tegea and GSL Dorothea [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						36 months
GSL Maria, GSL Violetta, GSL Arcadia, GSL MYNY, GSL Melita, GSL Tegea and GSL Dorothea [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						38 months
GSL Château d’If and CMA CGM Alcazar [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						36 months
GSL Château d’If and CMA CGM Alcazar [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						38 months
GSL Melina [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						35 months
GSL Melina [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						37 months
GSL Elizabeth [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						24 months
GSL Elizabeth [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						27 months
GSL Maren [Member] \| Minimum [Member]
Description of Business [Abstract]
Vessels charter fixed term						24 months
GSL Maren [Member] \| Maximum [Member]
Description of Business [Abstract]
Vessels charter fixed term						26 months
Vessels Purchase Agreement [Member] \| Four High Reefer ECO Vessels [Member]
Description of Business [Abstract]
Vessel capacity (in TEU) \| TEU				9,019
Number of newbuilding vessels to be purchased (in Vessel)				4
Aggregate purchase price (in Dollars) \| $				$ 273,891
Number of vessels delivered (in Vessel)				3
Vessels Purchase Agreement [Member] \| Tasman, Keta and Akiteta [Member]
Description of Business [Abstract]
Number of vessels sold (in Vessel)			3
Vessels Purchase Agreement [Member] \| Three Eco 8,586 TEU Vessels [Member]
Description of Business [Abstract]
Vessel capacity (in TEU) \| TEU		8,586
Number of newbuilding vessels to be purchased (in Vessel)		3
Aggregate purchase price (in Dollars) \| $		$ 90,000
Number of vessels delivered (in Vessel)		2						1
Vessels Purchase Agreement [Member] \| New Fifteen Vessels [Member]
Description of Business [Abstract]
Aggregate purchase price (in Dollars) \| $						$ 1,329,863
Number of vessels under construction (in Vessel)						15
Vessels Sale Agreement [Member] \| Ian H, Manet, Kumasi, and Julie [Member]
Description of Business [Abstract]
Number of vessels to be sold (in Vessel)						4
Aggregate sale price of vessels (in Dollars) \| $						$ 65,500