Note 8 - Goodwill and Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Carrying Amount	$ 169,123	$ 74,208
Accumulated Amortization	(49,252)	(40,989)
Net	$ 119,871	33,219
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	3 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	16 years
Intellectual Property [Member]
Carrying Amount	$ 15,731	7,690
Accumulated Amortization	(6,454)	(5,301)
Net	$ 9,277	2,389
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	9 years 182 days
Intellectual Property [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Intellectual Property [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	15 years
Trade Names [Member]
Carrying Amount	$ 5,839	3,739
Accumulated Amortization	(2,855)	(2,542)
Net	$ 2,984	1,197
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	4 years 146 days
Trade Names [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Trade Names [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Customer Relationships [Member]
Carrying Amount	$ 146,106	61,198
Accumulated Amortization	(38,777)	(31,584)
Net	$ 107,329	29,614
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	9 years 182 days
Customer Relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Customer Relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Noncompete Agreements [Member]
Carrying Amount	$ 1,447	1,581
Accumulated Amortization	(1,166)	(1,562)
Net	$ 281	$ 19
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	4 years 146 days
Noncompete Agreements [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Noncompete Agreements [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

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