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Earnings Per Share / Unit (EPS / EPU) - Additional Information (Details) - shares | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
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Service Awards/Service Units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested Service Awards / Performance Awards | 211,920 | 296,371 |
Service Awards/Service Units | Management |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested Service Awards / Performance Awards | 211,920 | 296,371 | 405,436
First Industrial, L.P. |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested Service Awards / Performance Awards | 444,407 | 421,928 | 405,436

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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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. + References No definition available. + Details
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