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Debt (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Debt |
Schedule of carrying value of Convertible Senior Notes |
|  | December 31,
|  | 2018 |  | 2017
|  | (in thousands)
Principal amount |  | $ | 345,000 |  | $ | 345,000
Unamortized debt discount |  |  | (52,336) |  |  | (63,022)
Unamortized transaction costs |  |  | (5,272) |  |  | (6,348)
Net carrying value |  | $ | 287,392 |  | $ | 275,630
Schedule of interest expense related to Convertible Senior Notes |
|  | For the year ended December 31,
|  | 2018 |  | 2017
|  | (in thousands)
Cash Interest Expense |  |  |  |  |  |
Coupon interest expense |  | $ | 9,315 |  | $ | 8,901
Non-Cash Interest Expense |  |  |  |  |  |
Amortization of debt discount |  |  | 10,686 |  |  | 9,490
Amortization of transaction costs |  |  | 1,076 |  |  | 956
Total Interest Expense |  | $ | 21,077 |  | $ | 19,347

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- 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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- Definition Tabular disclosure of interest income and expense, including, but not limited to, interest income and expense from investments, loans, and securities. + References No definition available. + Details
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