Note 5 - Income Taxes (Detail) - Temporary Differences Related to Deferred Income Taxes (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2011
Deferred income tax assets:
Post-retirement liability	$ 2,277	$ 2,520	$ 2,595
Deferred income	1,651	1,676	1,796
Stock based compensation	1,857	1,579	1,558
Federal operating loss carry-forwards	11,481	15,788	11,214
Capital loss carryforward	2,243	2,045
State tax credits	3,022	3,022	3,022
State operating loss carry-forwards	7,638	8,427	6,858
Other	4,626	4,833	3,947
Less: valuation allowance	(9,053)	(9,840)	(13,675)
Gross deferred income tax assets	25,742	30,050	17,315
Deferred income tax liabilities:
Fixed assets	(20,180)	(21,860)	(10,878)
Equity method investment	(526)	(1,999)	(1,939)
Other	(5,036)	(6,191)	(4,498)
Gross deferred income tax liabilities	$ (25,742)	$ (30,050)	$ (17,315)