Note 7 - Goodwill and Other Acquired Intangible Assets, Net - Schedule of Other Intangible Assets (Details) - Real Estate segment - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount	$ 52,298	$ 52,298
Other Intangible Assets, Accumulated Amortization and Impairment	(39,919)	(39,057)
Other Intangible Assets, Net Carrying Amount	12,379	13,241
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	(32,324)	(31,559)
Other Intangible Assets, Net Carrying Amount	11,226	11,991
Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount	8,285	8,285
Other Intangible Assets, Accumulated Amortization and Impairment	(7,446)	(7,370)
Other Intangible Assets, Net Carrying Amount	839	915
Licenses
Acquired Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets, Original Acquired Amount	463	463
Other Intangible Assets, Accumulated Amortization and Impairment	(149)	(128)
Other Intangible Assets, Net Carrying Amount	$ 314	$ 335