Equity Award, Conversion Basis

No definition available.

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- Definition

Number of Tranches

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No definition available.

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- Definition

Represents the number of trustees serving in the board of trustees of the reporting entity.

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- Definition

Share-based Compensation Arrangement, Plan Term

+ References

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 cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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.

+ References

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 non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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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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No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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

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- Definition

Number of shares issued during the period as a result of the conversion of convertible securities.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Value, before forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Share-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands									12 Months Ended
	Jun. 23, 2021 USD ($) trustee $ / shares shares	Jan. 25, 2021 $ / shares shares	Sep. 16, 2020 USD ($) trustee $ / shares shares	Jun. 23, 2020 USD ($) trustee $ / shares shares	Jan. 27, 2020 $ / shares shares	Jun. 20, 2019 USD ($) trustee $ / shares shares	Jan. 29, 2019 $ / shares shares	Jun. 16, 2015	Dec. 31, 2025 shares	Dec. 31, 2024 shares	Dec. 31, 2023 shares	Dec. 31, 2022 shares	Dec. 31, 2021 USD ($) tranche $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for issuance (in shares)													1,526,730
Number of independent trustees \| trustee	6		9	9		9
Common stock issued (in shares)													115,205,818	121,522,555	384,811
Compensation expense, accelerated vesting due to a staffing reduction \| $													$ 3,500	$ 17	$ 800
Equity Commonwealth 2015 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)						2,500,000
Share-based compensation arrangement, plan term								10 years
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $													$ 15,400	$ 13,200	$ 14,400
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)	18,505	122,466	2,526		85,058	23,520	112,359
Granted (in dollars per share) \| $ / shares		$ 28.25	$ 30.39		$ 32.81		$ 31.77
Common stock issued (in shares)													523,662
Stock issued during period, value \| $			$ 100
Restricted shares \| Independent Trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)				19,104
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period													3 years
Number of tranches \| tranche													2
Vested (in shares)													523,662	388,615	384,811
Common stock issued (in shares)														388,615
RSUs \| Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage													50.00%
RSUs \| Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period													1 year
Vesting percentage													50.00%
RSUs, target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)		248,646			172,697		228,128
RSUs, maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)		619,750			430,447		568,609
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity award, conversion basis													1
Number of equity awards granted (in shares)				9,552
Time-Based LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)	3,701					2,940
Market-Based LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (in shares)													81,434	84,754
Conversion of equity instruments (in shares)													(81,434)	(84,754)
Market-Based LTIP Units, target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)					40,841
Market-Based LTIP Units, maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)					101,796
Time-Based LTIP Units, target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)					20,116
OP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of equity instruments (in shares)													81,434	84,754
Restricted Shares and Time-Based LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Number of equity awards granted (in shares)				3,184									144,672	136,356	138,819
Granted (in dollars per share) \| $ / shares													$ 28.06	$ 32.47	$ 32.20
Share based compensation amount \| $	$ 100			$ 100		$ 100
Price per share (in dollars per share) \| $ / shares	$ 27.02			$ 31.41		$ 34.01
Vested (in shares)													188,990	149,103	164,074
Unvested (in shares)													341,370	385,688	400,314	425,888
Estimated future compensation expense for unvested shares \| $													$ 5,000
Weighted average period over which compensation expense will be recorded													2 years 3 months 18 days
Restricted Shares and Time-Based LTIP Units \| Independent Trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)	3,701					2,940
Restricted Shares and Time-Based LTIP Units \| Scenario, Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (in shares)									53,018	62,206	91,181	134,965
RSUs and Market-Based LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)													619,750	532,243	568,609
Granted (in dollars per share) \| $ / shares													$ 15.19	$ 16.12	$ 15.91
Vested (in shares)													605,096	473,369	384,811
Unvested (in shares)													1,979,572	1,964,918	2,003,175	2,046,644
Estimated future compensation expense for unvested shares \| $													$ 10,400
Weighted average period over which compensation expense will be recorded													2 years 1 month 6 days
Maximum \| Equity Commonwealth 2015 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for issuance (in shares)													5,750,000