Earnings Per Share (Computation Of Basic And Diluted Earnings (Loss) Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net income (loss) attributable to RDI common shareholders	$ (5,875)	$ (2,125)
Weighted average shares of common stock – basic	21,752,371	22,920,486
Weighted average dilutive impact of awards	367,250	203,620
Weighted average number of common stock – diluted	22,119,621	23,124,106
Basic earnings (loss) per share attributable to RDI common stockholders	$ (0.27)	$ (0.09)
Diluted earnings (loss) per share attributable to RDI common stockholders	$ (0.27)	$ (0.09)
Awards excluded from diluted earnings (loss) per share	678,377	496,089