Note B - Acquisition of Veth Propulsion Holding BV (Details Textual) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
		Jul. 02, 2018	Dec. 28, 2018	Dec. 29, 2017	Dec. 28, 2018	Dec. 29, 2017
Proceeds from Issuance of Long-term Debt, Total					$ 35,000
Payments to Acquire Businesses, Net of Cash Acquired, Total					59,651
Amortization of Inventory Fair Value Step-up					2,173
Amortization of Intangible Assets, Total			$ 583	$ 45	1,249	89
The 2018 Credit Agreement [Member]
Proceeds from Issuance of Long-term Debt, Total		$ 60,729
Payments to Acquire Businesses, Net of Cash Acquired, Total		59,651
Cash Acquired from Acquisition		1,078
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Restricted Cash		$ 685
Veth Propulsion [Member]
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Payments to Acquire Businesses, Gross	[1]	$ 60,729
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		$ 3,800
Percentage of Work in Process of Inventory Completed		70.00%
Inventory, Net, Step-up Value Amount		$ 4,402
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total	[2]	$ 2,641
Amortization of Inventory Fair Value Step-up			1,002	1,179	2,173	2,358
Amortization of Intangible Assets, Total			647		1,268
Business Combination, Acquisition Related Costs			$ 256		$ 460
Amortization of Intangible Assets and Interest Expense of Long-term Debt, Total, Before Tax				$ 1,136		$ 2,271
Veth Propulsion [Member] | Het Komt Vast Goed B.V. [Member]
Lessee, Operating Lease, Term of Contract		15 years
Lessee, Operating Lease, Annual Rent Payments		$ 1,249
Veth Propulsion [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life		2 years
Veth Propulsion [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life		13 years

[1] In the statement of cash flows, the cash used in the acquisition of Veth Propulsion in the amount of $59,651 is net of the cash, including restricted cash, acquired in the transaction, of $1,078 (see below for fair value of assets acquired and liabilities assumed).

[2] The fair value of property, plant and equipment is estimated at $2,641. These assets primarily consist of manufacturing equipment, test equipment, vehicles, and office and plant fixtures. Their estimated useful lives range from 2 to 13 years.