Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Note 5 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Oct. 01, 2019	Jan. 01, 2018
Long-term Debt, Fair Value			$ 146,400	$ 117,900
Long-term Debt, Gross			143,700	114,200
Goodwill, Impairment Loss		$ 8,891	0	0
Goodwill, Ending Balance	$ 10,778	10,778	21,993	19,817	$ 10,778	$ 20,177
North America Reporting Unit [Member]
Goodwill, Impairment Loss	8,900
Goodwill, Impairment Loss, Net of Tax	8,500
Europe Reporting Unit [Member]
Goodwill, Ending Balance	$ 10,800	$ 10,800
Fair Value, Nonrecurring [Member]
Assets, Fair Value Disclosure			0	0
Investments Held in Rabbi Trust [Member]
Debt Securities, Available-for-sale, Total			$ 1,100	$ 1,400