Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Accounting Policies [Abstract] | |||
| Operating lease revenue | $ 3,409 | $ 3,162 | $ 2,198 |
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- References No definition available.
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- Definition The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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