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- Definition

Number of Tranches

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- Definition

Share-Based Payment Arrangement, Term

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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No definition available.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- 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.

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Percentage of vesting of award under share-based payment arrangement.

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Share-Based Compensation - Narrative (Details)			1 Months Ended	3 Months Ended
Share-Based Compensation - Narrative (Details)	Feb. 04, 2025	Jan. 29, 2024 $ / shares shares	Feb. 28, 2025	Mar. 31, 2025 tranche shares	Mar. 31, 2024 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense, accelerated vesting due to a staffing reduction \| $					$ 0
Equity Commonwealth 2015 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Payment Arrangement, Term				10 years
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $					$ 2,600,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)				3 years
Number of tranches \| tranche				2
Share-based compensation arrangement, shares vested in period (in shares)				873,406	391,061
Common shares of beneficial interest, shares issued (in shares)				873,406	391,061
RSUs \| Vesting in three years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	50.00%			50.00%
RSUs \| Vesting in four years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)				1 year
Vesting percent			50.00%	50.00%
RSUs at target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)		288,596
RSUs at maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)		719,326
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion basis				1
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)		142,146
Granted shares value (in dollars per share) \| $ / shares		$ 19.36
RSUs and Market-Based LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares value (in dollars per share) \| $ / shares		$ 27.08