Note 7 - Inventories - Fair Value of Impaired Inventory (Details) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Impairment Data; Total Subdivisions Tested	40	25	17	14	15	18	22	22	21	23	16	16
Impairment Data; Inventory Impairments	$ 3,873	$ 4,700	$ 1,600		$ 5,200	$ 3,225		$ 350	$ 910		$ 850		$ 10,173	$ 8,775	$ 1,760
Impairment Data; Fair Value of Inventory After Impairments	$ 23,657	$ 12,295	$ 6,415		$ 19,925	$ 14,836		$ 3,701	$ 4,646		$ 4,285		$ 42,367	$ 38,462	$ 8,931
Impairment Data; Number of Subdivisions Impaired	3	2	2		3	5		1	2		2		7	9	4
Quantitative Data; Discount Rate								9.00%	13.00%
Minimum [Member]
Quantitative Data; Discount Rate	12.00%	15.00%	12.00%		15.00%	12.00%					11.00%		5.00%
Maximum [Member]
Quantitative Data; Discount Rate	15.00%	18.00%	15.00%		20.00%	15.00%					14.00%		12.00%