Note 6 - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Deferred compensation plan	$ 5,072	$ 4,719
Foreign currency forward contracts	1	101
Total financial assets	5,073	4,820
Foreign currency forward contracts	(18)
Fair Value, Inputs, Level 1 [Member]
Deferred compensation plan	4,270	3,925
Foreign currency forward contracts
Total financial assets	4,270	3,925
Foreign currency forward contracts
Fair Value, Inputs, Level 2 [Member]
Deferred compensation plan	802	794
Foreign currency forward contracts	1	101
Total financial assets	803	895
Foreign currency forward contracts	(18)
Fair Value, Inputs, Level 3 [Member]
Deferred compensation plan
Foreign currency forward contracts
Total financial assets
Foreign currency forward contracts

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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-SubTopic 10
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-Paragraph 2
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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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