Fair Value Measurements (Details) - USD ($) $ in Thousands |
9 Months Ended | |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Assets and liabilities measured at fair value | ||
| Marketable securities in deferred compensation plan | $ 4,346 | $ 4,616 |
| Deferred compensation plan | Trustees and Management | ||
| Assets and liabilities measured at fair value | ||
| Maximum percentage of participants' compensation which is deferrable (as a percent) | 100.00% | |
| Marketable securities in deferred compensation plan | $ 4,300 |
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- Definition Represents the maximum percentage of participants' compensation that is deferrable by participants under the deferred compensation plan. No definition available.
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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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