XML 46 R37.htm IDEA: XBRL DOCUMENT
v3.22.1

Note 12 - Convertible Senior Notes (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2022
Notes Tables |
Convertible Debt [Table Text Block] |
|  | March 31, |  |  | December 31, |
​ |  | 2022 |  |  | 2021 |
Principal |  | $ | 80,500 |  |  | $ | 80,500 |
Unamortized debt issuance costs |  |  | (1,616 | ) |  |  | (1,820 | )
Net carrying amount |  | $ | 78,884 |  |  | $ | 78,680 |
Interest Income and Interest Expense Disclosure [Table Text Block] |
|  | Three months ended March 31, |
​ |  | 2022 |  |  | 2021 |
Contractual interest expense |  | $ | 1,006 |  |  | $ | 1,006 |
Amortization of debt issuance costs |  |  | 204 |  |  |  | 204 |
Total interest cost |  | $ | 1,210 |  |  | $ | 1,210 |
Effective interest rate |  |  | 5.1 | % |  |  | 5.1 | %

X
- Definition Tabular disclosure of convertible debt instrument. Includes, but is not limited to, principal amount and amortized premium or discount. + References No definition available. + Details
Name: | us-gaap_ConvertibleDebtTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_InterestIncomeAndInterestExpenseDisclosureTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_TableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration