Note 1 - Summary of Significant Interim Accounting Policies - Impact of New Standard on Consolidated Balance Sheet (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Contract assets		$ 46,826	$ 46,800	$ 43,300
Inventory	[1]	67,852			64,979
Prepaid and other current assets		10,830			11,011
Deferred taxes		(8,900)
Accounts payable		22,337			19,752
Other current liabilites		11,327			$ 12,409
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Contract assets
Inventory		94,692
Prepaid and other current assets		11,791
Deferred taxes		(6,014)
Accounts payable		19,841
Other current liabilites		10,023
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Contract assets		46,826
Inventory		(26,840)
Prepaid and other current assets		(961)
Deferred taxes		(2,886)
Accounts payable		2,496
Other current liabilites		$ 1,304

[1] Inventories consist of the following: June 30, 2018 (Unaudited) December 31, 2017 Finished goods $ 58,633 $ 54,354 Work in process 939 604 Raw materials 8,280 10,021 $ 67,852 $ 64,979