Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net income attributable to RDI common stockholders	$ 4,999	$ 19,032	$ 8,045	$ 22,063	[1]
Weighted average number of common stock – basic	22,933,589	23,148,995	22,979,436	23,168,703	[1]
Weighted average dilutive impact of awards	213,784	247,148	213,784	247,148
Weighted average number of common stock – diluted	23,147,373	23,396,143	23,193,220	23,415,851	[1]
Basic EPS attributable to RDI common stockholders	$ 0.22	$ 0.82	$ 0.35	$ 0.95	[1]
Diluted EPS attributable to RDI common stockholders	$ 0.22	$ 0.81	$ 0.35	$ 0.94	[1]
Awards excluded from diluted EPS	126,840	149,841	126,840	149,841

[1] Certain prior year balances have been reclassified to conform to the 2018 presentation (see Note 2 - Summary of Significant Accounting Policies - Reclassifications).