| CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended | |
|---|---|---|
| Dec. 31, 2018 | Dec. 31, 2017 | |
| Common stock | ||
| Cash flows from financing activities | ||
| Stock issuance costs | $ 347 | $ 4,774 | 
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- References No definition available. 
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- Definition The cash outflow for cost incurred directly with the issuance of an equity security. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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