Note 6 - Goodwill and Intangible Assets - Summary of Acquired Amortizable Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 271,858	$ 197,205
Accumulated Amortization	(24,159)	(10,000)
Net Carrying Amount	247,699	187,205
Internal-use Software [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,132	7,026
Accumulated Amortization	(3,833)	(2,912)
Net Carrying Amount	$ 4,299	$ 4,114
Internal-use Software [Member] | Minimum [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Period (Year)	3 years	3 years
Internal-use Software [Member] | Maximum [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Period (Year)	7 years	7 years
Technology-based Intangibles [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Period (Year)	20 years	20 years
Gross Carrying Amount	$ 3,310	$ 3,481
Accumulated Amortization	(1,572)	(1,523)
Net Carrying Amount	1,738	1,958
Customer-related Intangibles [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	260,416	186,698
Accumulated Amortization	(18,754)	(5,565)
Net Carrying Amount	$ 241,662	$ 181,133
Customer-related Intangibles [Member] | Minimum [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Period (Year)	10 years	10 years
Customer-related Intangibles [Member] | Maximum [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Period (Year)	15 years	15 years