Note 4 - Fair Value Measurements and Derivative Financial Instruments - Summary of Gains and Losses Before Income Taxes on Interest Rate Swap Cash Flow Hedges (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Gain recognized in accumulated other comprehensive loss	$ 47	$ 107	$ 34	$ 412
Interest Rate Swap [Member] \| Cash Flow Hedging [Member]
Gain recognized in accumulated other comprehensive loss	47	107	34	412
Gain reclassified from accumulated other comprehensive loss to income	$ 224	$ 97	$ 451	$ 122

Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
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-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

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