Note 17 - Retirement Plans - Expected Benefit Payments (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Pension Plan [Member] \| UNITED STATES
2018	$ 3,321
2019	3,397
2020	3,463
2021	3,504
2022	3,534
2023-2027	17,350
Pension Plan [Member] \| Foreign Plan [Member]
2018	817
2019	867
2020	861
2021	848
2022	954
2023-2027	5,344
Supplemental Employee Retirement Plan [Member]
2018	609
2019
2020
2021
2022
2023-2027

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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