Note 7 - Notes Payable (Details Textual) - USD ($)				12 Months Ended
	Oct. 22, 2018	Oct. 21, 2018	Feb. 17, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 03, 2018	Jan. 25, 2016
Amortization of Debt Issuance Costs				$ 476,000	$ 4,823,000	$ 1,397,000
Write off of Deferred Debt Issuance Cost			$ 140,000
Debt Issuance Costs, Current, Net, Total							$ 2,100,000
Senior Notes [Member]
Debt Issuance Costs, Gross				4,900,000
Amortization of Debt Issuance Costs					896,000
Write off of Deferred Debt Issuance Cost					3,070,000
Legal Fees					14,000
Subordinated Debt [Member]
Debt Issuance Costs, Gross				892,000
Amortization of Debt Issuance Costs					133,000
Write off of Deferred Debt Issuance Cost					621,000
Legal Fees					14,000
Previous Credit Facility [Member]
Debt Issuance Costs, Gross					2,700,000
Amortization of Debt Issuance Costs						141,000
Write off of Deferred Debt Issuance Cost						140,000
Legal Fees						15,000
Line of Credit Facility, Maximum Borrowing Capacity						5,000,000
Long-term Line of Credit, Total						0
New Credit Facility [Member]
Debt Issuance Costs, Gross				2,100,000
Amortization of Debt Issuance Costs				476,000	75,000
Line of Credit Facility, Maximum Borrowing Capacity				5,000,000
Long-term Line of Credit, Total				0
Line of Credit Facility, Commitment Fee Percentage	0.38%	0.50%
Line of Credit Facility, Commitment Fee Amount				24,000	$ 4,000
Debt Issuance Costs, Current, Net, Total				$ 446,000
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity								$ 5,000,000
Line of Credit Facility, Commitment Fee Percentage					0.75%
Line of Credit Facility, Commitment Fee Amount					$ 32,000	$ 33,000