Note 6 - Debt - Notes Payable, Lines of Credit and Credit Facilities (Details) (Parentheticals) - Line of Credit [Member] - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Facility to Finance Acquisition of Portfolio [Member]
Credit facility, maximum borrowing capacity	$ 0
CNB [Member]
Credit facility, maximum borrowing capacity	0	25,000
CNB [Member] \| Revolving Credit Facility [Member]
Credit facility, maximum borrowing capacity	$ 0	$ 20,000

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant