Note 3 - Revenue (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Disaggregation of Revenue [Table Text Block]

Product Category
	2021		2020		2019
Pumps and pump systems	$	321,263	$	300,906	$	341,304
Repair parts for pumps and pump systems and other		57,053		48,061		56,875
Total net sales	$	378,316	$	348,967	$	398,179
Geographic Location
	2021		2020		2019
United States	$	260,683	$	246,913	$	275,290
Foreign countries		117,633		102,054		122,889
Total net sales	$	378,316	$	348,967	$	398,179

Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]

	December 31, 2021		December 31, 2020
Contract assets	$	-	$	-
Contract liabilities		9,200		8,004