Note 3 - (Loss) Earnings Per Share - Basic and Diluted Net Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Net (loss) earnings	$ (6,490)	$ 2,967	$ 1,131	$ 11,352	$ 6,634	$ (1,303)	$ (2,391)	$ 16,684
Undistributed (loss) earnings	(7,331)			10,533			(4,907)	14,214
Common Class A [Member]
Net (loss) earnings	(1,112)			1,942			(442)	2,852
Less dividends declared	131	131	130	130	131	130	392	391
Undistributed (loss) earnings	$ (1,243)			$ 1,812			$ (834)	$ 2,461
Weighted-average shares outstanding, basic and diluted (in shares)	2,173			2,175			2,174	2,175
Net earnings per share, basic and diluted (in dollars per share)	$ (0.51)			$ 0.89			$ (0.20)	$ 1.31
Common Class B [Member]
Net (loss) earnings	$ (5,378)			$ 9,410			$ (1,949)	$ 13,832
Less dividends declared	710	$ 704	$ 708	689	$ 689	$ 700	2,124	2,079
Undistributed (loss) earnings	$ (6,088)			$ 8,721			$ (4,073)	$ 11,753
Weighted-average shares outstanding, basic and diluted (in shares)	10,139			9,972			10,113	9,891
Net earnings per share, basic and diluted (in dollars per share)	$ (0.53)			$ 0.94			$ (0.19)	$ 1.40

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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