Note 6 - Goodwill and Other Acquired Intangible Assets, Net Schedule of Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Acquired Finite-Lived Intangible Assets [Line Items]
Goodwill and Intangible Asset Impairment	$ 0
Real Estate segment
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount		$ 52,778	$ 52,928
Other Intangible Assets, Accumulated Amortization and Impairment		(36,351)	(34,543)
Other Intangible Assets, Net Carrying Amount		16,427	18,385
Real Estate segment | Client relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount		43,550	43,550
Other Intangible Assets, Accumulated Amortization and Impairment		(28,921)	(27,269)
Other Intangible Assets, Net Carrying Amount		14,629	16,281
Real Estate segment | Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount		8,285	8,435
Other Intangible Assets, Accumulated Amortization and Impairment		(6,884)	(6,789)
Other Intangible Assets, Net Carrying Amount		1,401	1,646
Real Estate segment | Trade name and trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount		480	480
Other Intangible Assets, Accumulated Amortization and Impairment		(442)	(404)
Other Intangible Assets, Net Carrying Amount		38	76
Real Estate segment | Licenses
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount		463	463
Other Intangible Assets, Accumulated Amortization and Impairment		(104)	(81)
Other Intangible Assets, Net Carrying Amount		$ 359	$ 382