Face (par) amount of the original debt instrument that was repurchased and retired.

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Represents a general basket base limit value amount before other items are included.

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The amount of maximum quarterly repurchases during the period.

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The amount of net worth covenant for a line of credit facility.

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Represents the percent of consolidated net income (loss) included in a general basket limitation for determining if restricted payments can be made.

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Represents the percent of consolidated tangible net assets included in a general basket limitation for determining if restricted payments can be made.

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Represents the offering price of the notes issued as a percentage of their face amount.

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Represents the percent of net cash proceeds from qualified equity offerings included in a general basket limitation for determining if restricted payments can be made.

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The cash inflow received from loan funding under the Paycheck Protection Program which was established under the Coronavirus Aid, Relief and Economic Security (CARES) Act in March 2020.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt premium.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Gross amount of debt extinguished.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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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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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The effective interest rate at the end of the reporting period.

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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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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Note 9 - Senior Notes and Unsecured Revolving Credit Facility (Details Textual) - USD ($)		3 Months Ended		6 Months Ended
	Apr. 15, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 26, 2020	Jun. 25, 2020	Dec. 31, 2019	May 04, 2017	Mar. 17, 2017
Early Repayment of Senior Debt				$ 9,825,000	$ 10,856,000
Gain (Loss) on Extinguishment of Debt, Total		$ 702,000	$ 552,000	579,000	969,000
Proceeds from Paycheck Protection Program Under CARES Act	$ 7,000,000.0
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity						$ 60,000,000	$ 130,000,000
Line of Credit Facility, Net Worth Covenant						150,000,000	180,000,000
Long-term Line of Credit, Total		$ 0		$ 0				$ 0
Line of Credit Facility, Interest Rate at Period End		5.00%		5.00%
Revolving Credit Facility [Member] \| Other Assets [Member]
Debt Issuance Costs, Net, Total		$ 500,000		$ 500,000
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate				3.50%
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate				4.50%
Accordion Feature [Member]
Line of Credit Facility, Maximum Borrowing Capacity						150,000,000	$ 200,000,000
Letter of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity		10,000,000.0		$ 10,000,000.0
Letters of Credit Outstanding, Amount		$ 0		$ 0				$ 0
Net Leverage Ratio, Greater Than 55% [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Quarterly Repurchases						0
Net Leverage Ratio, Less Than or Equal to 55% [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Quarterly Repurchases						5,000,000
Net Leverage Ratio Less Than or Equal to 50% [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Quarterly Repurchases						$ 10,000,000
Senior Notes [Member] \| Senior Notes Due 2022 [Member]
Debt Instrument, Face Amount										$ 250,000,000
Debt Instrument, Interest Rate, Stated Percentage		7.25%		7.25%				7.25%		7.25%
Percent of Debt Instrument Face Amount, Value Issued										98.961%
Debt Instrument, Interest Rate, Effective Percentage										7.50%
Debt Instrument, Unamortized Discount, Total		$ 800,000		$ 800,000				$ 1,100,000
Debt Instrument, Unamortized Premium, Total		600,000		600,000				900,000
Debt Issuance Costs, Net, Total		$ 2,200,000		$ 2,200,000				$ 3,000,000.0
Percent of Consolidated Net Income, General Basket Limitation for Restricted Payments to be Made		50.00%		50.00%
Percent of Net Cash Proceeds From Qualified Equity Offerings, General Basket Limitation for Restricted Payments to be Made		100.00%		100.00%
Percent of Consolidated Tangible Net Assets, General Basket Limitation for Restricted Payments to be Made		15.00%		15.00%
General Basket, Value		$ 15,000,000		$ 15,000,000
Extinguishment of Debt, Amount		5,800,000		10,500,000
Early Repayment of Senior Debt		5,000,000.0	6,300,000	9,800,000	10,900,000
Gain (Loss) on Extinguishment of Debt, Total		700,000		600,000	1,000,000.0
Write off of Deferred Debt Issuance Cost		49,000	90,000	95,000	160,000
Debt Instrument, Repurchased and Retired, Face Amount			$ 7,000,000.0		$ 12,000,000.0
Senior Notes [Member] \| Senior Notes Due 2022, Additional [Member]
Debt Instrument, Face Amount									$ 75,000,000
Debt Instrument, Interest Rate, Stated Percentage									7.25%
Percent of Debt Instrument Face Amount, Value Issued									102.75%
Debt Instrument, Interest Rate, Effective Percentage									6.438%
Debt Instrument, Unamortized Discount, Total		800,000		800,000
Debt Instrument, Unamortized Premium, Total		600,000		600,000
Debt Issuance Costs, Net, Total		2,200,000		2,200,000
Existing or Future Bank Credit Facilities [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 260,000,000		$ 260,000,000