Note 11 - Accrued Pension Liabilities - Assumptions Used in the Measurement of the Pension Expense and Benefit Obligation (Details)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Discount rate	1.10%	1.90%	1.80%
Rate of compensation increase	2.50%	2.50%	2.50%

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Balance Type:	na
Period Type:	instant