The amount of investment over the next four years that is required under the covenant of the debt instrument.

No definition available.

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The effective annual yield of the debt instrument.

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Represents the discount rate for debt instrument issued.

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No definition available.

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The number of issuance installments for a debt instruments.

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No definition available.

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Percentage price of original principal amount of debt, including accrued and unpaid interest, at which debt can be redeemed by the issuer.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer, net of cash proceeds of equity offerings.

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No definition available.

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The percentage of principal of the premium on the debt instrument at the time of issuance.

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No definition available.

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Percentage of fronting fee to each issuing bank annually on the average dollar amount of any outstanding letters of credit.

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No definition available.

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The percentage of required participation fee on the letter of credit.

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No definition available.

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Represents the amount available for refinance under a line of credit facility.

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No definition available.

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Represents the underwriting discount on senior notes.

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No definition available.

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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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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount, after accumulated amortization, of debt discount.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt premium.

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- Definition

Amount of interest expense on finance lease liability.

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-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Discount rate used by lessee to determine present value of operating lease payments.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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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Amount of operating lease expense. Excludes sublease income.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Note 9 - Debt, Credit Facility and Leases (Details Textual) $ in Thousands, shares in Millions, $ in Millions						1 Months Ended		9 Months Ended
	Oct. 09, 2020 CAD ($)	Sep. 09, 2020 CAD ($)	Aug. 09, 2020 CAD ($)	Jul. 09, 2020 CAD ($)	Mar. 19, 2020 USD ($)	Dec. 31, 2019 USD ($) shares	Dec. 31, 2019 CAD ($) shares	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jul. 09, 2020 USD ($)	Jul. 09, 2020 CAD ($)	Feb. 19, 2020 USD ($)	Jul. 31, 2018 USD ($)	Mar. 05, 2018 USD ($)	Mar. 05, 2018 CAD ($)	May 31, 2016 USD ($)
Proceeds from Issuance of Long-term Debt, Total								$ 707,107	$ 245,000
Amortization of Debt Discount (Premium)								5,500	5,100
Payments of Debt Issuance Costs								1,287	587
Letters of Credit Outstanding, Amount								20,300
Finance Lease, Liability, Total						$ 12,600		14,070
Finance Lease, Liability, Current						5,429		6,187
Finance Lease, Liability, Noncurrent						7,214		7,883
Finance Lease, Right-of-Use Asset, after Accumulated Amortization, Total						20,600		20,800
Finance Lease, Interest Expense								400	600
Finance Lease, Liability, Payment, Due, Total								14,989
Finance Lease, Liability, Undiscounted Excess Amount								$ 919
Finance Lease, Weighted Average Remaining Lease Term (Year)								1 year 10 months 24 days
Finance Lease, Weighted Average Discount Rate, Percent								6.80%
Operating Lease, Liability, Total								$ 11,945
Operating Lease, Liability, Current						5,580		3,590
Operating Lease, Liability, Noncurrent						10,818		8,355
Operating Lease, Right-of-Use Asset						$ 16,381		11,928
Operating Lease, Expense								4,700	5,700
Lessee, Operating Lease, Liability, to be Paid, Total								$ 13,602
Operating Lease, Weighted Average Remaining Lease Term (Year)								5 years 3 months 18 days
Maximum [Member]
Lessee, Operating Lease, Discount Rate								6.50%
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity													$ 250,000
Line of Credit Facility, Amount Available for Refinance																$ 100,000
Proceeds from Lines of Credit, Total								$ 210,000
Repayments of Lines of Credit								210,000
Long-term Line of Credit, Total								0
Letter of Credit [Member]
Letter of Credit Outstanding, Fronting Fee													0.20%
Letter of Credit [Member] \| Minimum [Member]
Letter of Credit, Participation Fee, Percent													2.25%
Letter of Credit [Member] \| Maximum [Member]
Letter of Credit, Participation Fee, Percent													4.00%
Conversion of Series 2018A Senior Notes Into Common Stock [Member]
Interest Expense, Debt, Total								1,100
Debt Conversion, Converted Instrument, Shares Issued (in shares) \| shares						10.7	10.7
Debt Conversion, Converted Instrument, Amount						$ 33,500	$ 43.8
Senior Notes [Member] \| The 2028 Senior Notes [Member]
Debt Instrument, Face Amount												$ 475,000
Debt Instrument, Interest Rate, Stated Percentage												7.25%
Proceeds from Issuance of Long-term Debt, Total					$ 469,500
Long-term Debt, Gross								475,000
Underwriting Discount on Senior Notes												1.16%
Debt Instrument, Unamortized Discount, Total												$ 5,500
Interest Expense, Debt, Total								31,400	$ 27,200
Long-term Debt, Total								$ 468,300
Debt Instrument, Redemption Price, Percentage								100.00%
Debt Instrument, Redemption Price, Percentage, Net of Cash Proceeds of Equity Offerings								35.00%
Debt Instrument, Redemption Price, Percentage								101.00%
Senior Notes [Member] \| The 2021 Senior Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage						6.875%
Long-term Debt, Gross						$ 506,500
Amortization of Debt Discount (Premium)					$ 1,700
Long-term Debt, Total						504,700
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total								$ 6,700
Debt Instrument, Unamortized Discount (Premium), Net, Total						$ 1,800
Senior Notes [Member] \| IQ Notes [Member]
Debt Instrument, Face Amount										$ 36,800	$ 50.0
Debt Instrument, Interest Rate, Stated Percentage										6.515%	6.515%
Long-term Debt, Gross								27,100
Interest Expense, Debt, Total								300
Long-term Debt, Total								27,500			$ 48.2
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total								$ 400
Debt Instrument, Unamortized Premium, Percentage of Principal										103.65%	103.65%
Debt Instrument, Unamortized Premium, Total											$ 1.8
Debt Instrument, Effective Annual Yield										5.74%	5.74%
Debt Instrument, Number of Issuance Installments										4	4
Proceeds from Issuance of Debt		$ 12.5	$ 12.5	$ 12.5
Payments of Debt Issuance Costs				$ 0.6
Debt Instrument, Covenant, Investment Over Next Four Years											$ 100.0
Senior Notes [Member] \| IQ Notes [Member] \| Subsequent Event [Member]
Proceeds from Issuance of Debt	$ 12.5
Series 2018-A Senior Notes [Member]
Debt Instrument, Face Amount														$ 30,800	$ 40.0
Debt Instrument, Interest Rate, Stated Percentage														4.68%	4.68%
Debt Instrument, Unamortized Discount, Total															$ 0.2
Debt Instrument, Issuance, Discount Rate														0.58%	0.58%