Note 7 - Deferred Income Tax Asset (Liability) (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Deferred income tax assets:
Pension accruals	$ 3,678,000	$ 3,340,000
Operating reserves and other accruals	1,231,000	1,069,000
Tax carrying value in excess of book basis of goodwill	1,514,000	621,000
Deferred income tax liabilities:
Book carrying value in excess of tax basis of property	(691,000)	(572,000)
Deferred expenses	(752,000)	(1,013,000)
Net deferred income tax asset	$ 4,980,000	$ 3,445,000