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Debt (Tables) | 3 Months Ended
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Mar. 31, 2018
Debt [Abstract] |
Summary of Carrying Value of Convertible Notes | The table below summarizes the carrying value of the 2021 Convertible Notes as of March 31, 2018:
Principal amount |  | $ | 52,000 |
Discount |  |  | (12,916 | )
Carrying value as of March 31, 2018 |  | $ | 39,084 |

X
- Definition Tabular disclosure of borrowings which can be exchanged for a specified number of another security at the option of the issuer or the holder. Disclosures include, but are not limited to, principal amount, amortized premium or discount, and amount of liability and equity components. + References No definition available. + Details
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Balance Type: | na
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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration