Note 19 - Parent Company Financial Information - Statements of Cash Flows (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net (loss) income	$ (2,485,000)	$ (1,822,000)	$ 381,000	$ 426,000	$ 2,157,000	$ 2,322,000	$ 2,371,000	$ 1,777,000	$ (3,500,000)	$ 8,627,000	$ 8,905,000
Share based compensation									2,632,000	2,116,000	1,842,000
Amortization of debt issuance costs									6,000	6,000	29,000
Net cash used in operating activities									19,333,000	39,630,000	(984,000)
Net cash used in investing activities									(438,622,000)	(450,763,000)	(357,899,000)
Net proceeds from exercise of stock options									261,143	670,413	646,263
Net cash provided by financing activities									515,135,000	421,664,000	386,271,000
Decrease in cash									95,846,000	10,531,000	27,388,000
Cash and cash equivalents, beginning of year				72,473,000				61,942,000	72,473,000	61,942,000	34,554,000
Cash and cash equivalents, end of year	168,319,000				72,473,000				168,319,000	72,473,000	61,942,000
Parent Company [Member]
Net (loss) income									(3,500,000)	8,627,000	8,905,000
Share based compensation									2,632,000	2,116,000	1,842,000
Amortization of debt issuance costs									6,000	6,000	29,000
Increase in other assets									(1,069,000)	(1,639,000)	(1,342,000)
Net increase (decrease) in other liabilities									(18,000)	20,000	(179,000)
Equity in undistributed income of subsidiaries									293,000	(12,387,000)	(10,603,000)
Net cash used in operating activities									(1,656,000)	(3,257,000)	(1,348,000)
Investment in subsidiary									(20,000,000)	(30,000,000)
Net cash used in investing activities									(20,000,000)	(30,000,000)
Net proceeds from exercise of stock options									261,000	670,000	646,000
Net cash provided by financing activities									261,000	670,000	646,000
Decrease in cash									(21,395,000)	(32,587,000)	(702,000)
Cash and cash equivalents, beginning of year				$ 27,722,000				$ 60,309,000	27,722,000	60,309,000	61,011,000
Cash and cash equivalents, end of year	$ 6,327,000				$ 27,722,000				$ 6,327,000	$ 27,722,000	$ 60,309,000