Summary of Significant Accounting Policies - Contract Liabilities (Details) |
3 Months Ended |
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Mar. 31, 2019
USD ($)
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| Summary of Significant Accounting Policies | |
| Amounts included in contract liability at the beginning of the period | $ 2,686,000 |
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- References No definition available.
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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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