The amount of cash to be paid per $1,000 of principal held of convertible debt instruments, upon conversion.

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

+ References

No definition available.

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- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The number of shares outstanding as of the date of the statement of financial position in connection with an own-share lending arrangement entered into by the entity, in contemplation of a convertible debt offering or other financing.

+ References

No definition available.

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- Definition

The fair value as of the date of the statement of financial position of shares outstanding in connection with an own-share lending arrangement, in contemplation of a convertible debt offering or other financing.

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Note 11 - Convertible Senior Notes (Details Textual)			12 Months Ended
Note 11 - Convertible Senior Notes (Details Textual)	Aug. 26, 2019 USD ($)	Nov. 30, 2005 USD ($) shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares
Gain (Loss) on Repurchase of Debt Instrument				$ 5,127,000
Own-share Lending Arrangement, Shares, Outstanding (in shares) \| shares			1,459,233	1,459,233
Amortization of Debt Discount (Premium)			$ 585,000	$ 818,000
Bear Sterns International Limited [Member]
Own-share Lending Arrangement, Shares, Outstanding (in shares) \| shares		5,677,950	1,459,233
Own-share Lending Arrangement, Shares, Outstanding, Value			$ 35,900,000
Term Note [Member]
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Long-term Debt, Total	$ 17,400,000
Five Point Eight Seven Five Percent Convertible Senior Notes Due Two Thousand Thirty Five [Member]
Debt Instrument, Convertible, Conversion Price (in dollars per share) \| $ / shares			$ 24.61
Five Point Eight Seven Five Percent Convertible Senior Notes Due Two Thousand Thirty Five [Member] \| Convertible Debt [Member]
Debt Instrument, Face Amount	54,400,000	$ 300,000,000	$ 33,839,000	33,839,000
Debt Instrument, Interest Rate, Stated Percentage		5.875%
Debt Instrument, Maturity Date		Nov. 30, 2035
Debt Instrument, Repurchase Amount	16,300,000
Gain (Loss) on Repurchase of Debt Instrument	$ 5,100,000
Debt Instrument, Convertible, Conversion Ratio			40.63
Debt Instrument, Convertible, Conversion Price (in dollars per share) \| $ / shares			$ 24.61
Debt Instrument, Convertible, Cash Paid Per $1,000 Principal Held			$ 1,000
Amortization of Debt Discount (Premium)			300,000	500,000
Interest Payable			$ 2,000,000	$ 3,900,000
Debt, Weighted Average Interest Rate			9.20%	9.20%