Note 6 - Acquisitions - Amounts Assigned to Intangible Assets (Details) - The 2021 Acquisitions [Member] $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Total intangible assets	$ 11.4
Technology [Member]
Weighted average useful life (Year)	4 years
Total intangible assets	$ 3.1
Marketing [Member]
Weighted average useful life (Year)	5 years
Total intangible assets	$ 0.6
Customer [Member]
Weighted average useful life (Year)	12 years
Total intangible assets	$ 7.7

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration