Note 8 - Pension - Projected and Accumulated Benefit Obligation in Excess of Plan Assets (Details) - Pension Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Projected benefit obligation	$ 309,527	$ 352,572
Accumulated benefit obligation	303,789	349,311
Fair value of plan assets	260,365	304,084
UNITED STATES
Projected benefit obligation	268,232	322,594
Accumulated benefit obligation	268,232	322,594
Fair value of plan assets	260,365	304,084
Foreign Plan [Member]
Projected benefit obligation	41,295	29,978
Accumulated benefit obligation	35,557	26,717
Fair value of plan assets

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920

Name:	us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant