Stock Based Compensation - Trustee Awards and Total Compensation Expense Narrative (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Share-based compensation expense | $ 7,700,000 | $ 6,700,000 | $ 4,800,000 |
| Capitalized stock-based compensation expense | 200,000 | 300,000 | 200,000 |
| Trustee | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Fair value of share-based compensation for each trustee | $ 100,000 | $ 100,000 | $ 100,000 |
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The total fair value of shares issued during the period under a deferred compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cost capitalized for award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Details
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