Note 6 - Leases - Lease Expense (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating lease expense	[1]	$ 351	$ 560	$ 1,023	$ 1,196
Short-term lease expense		72	38	249	78
Land option expense		0	156	9	476
Total land option and lease expense		423	754	1,281	1,750
Cash flows from operating activities				600	969
Adoption of Topic 842				0	1,562
In exchange for new operating lease liabilities during the period				605	446
Office Leases [Member]
Operating lease expense		238	232	691	381
Land Leases [Member]
Operating lease expense		$ 113	$ 328	$ 332	$ 815

[1] Includes amortization of right-of-use assets for the three months ended March 31, 2020 and 2019 of $294 thousand and $184 thousand, respectively.