Summary Of Significant Accounting Policies (Accounting Changes To Consolidated Statements Of Income) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended										12 Months Ended
	Dec. 31, 2019	[1]	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	[1]	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue	$ 68,880		$ 70,386	$ 76,009	$ 61,493	$ 74,877		$ 74,150	$ 84,125	$ 75,779	$ 276,768	$ 308,931	$ 279,556
Operating income (loss)											9,123	23,624	20,383
Income (loss) before income taxes											2,334	17,464	34,169
Income tax benefit (expense)											28,837	3,298	3,293
Net income (loss)	(27,458)		801	2,294	(2,140)	4,926		1,177	5,028	3,035	(26,503)	14,166	30,876
Net income (loss) attributable to Reading International, Inc. common shareholders	$ (27,487)		$ 851	$ 2,331	$ (2,124)	$ 4,880		$ 1,215	$ 4,926	$ 3,013	$ (26,429)	$ 14,034	$ 30,865
Basic earnings (loss) per share	$ (0.99)		$ 0.04	$ 0.10	$ (0.09)	$ 0.21		$ 0.06	$ 0.22	$ 0.13	$ (1.17)	$ 0.61	$ 1.34
Diluted earnings (loss) per share	$ (0.99)		$ 0.04	$ 0.10	$ (0.09)	$ 0.21		$ 0.06	$ 0.22	$ 0.13	$ (1.17)	$ 0.60	$ 1.33
Real Estate [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue											$ 14,579	$ 15,208	$ 16,415
Cinema [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue											$ 262,189	293,723	263,141
Tax Year 2019 [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue												308,931	279,556
Operating income (loss)												23,623	20,383
Income (loss) before income taxes												17,463	34,169
Income tax benefit (expense)												(3,298)	(3,293)
Net income (loss)												14,166	30,876
Net income (loss) attributable to Reading International, Inc. common shareholders												$ 14,034	$ 30,865
Basic earnings (loss) per share												$ 0.61	$ 1.34
Diluted earnings (loss) per share												$ 0.60	$ 1.33
Tax Year 2019 [Member] | Cinema [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue												$ 293,723	$ 263,141
As Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue	$ 68,880		$ 70,456	$ 76,096	$ 61,551	$ 74,990		$ 74,261	$ 84,262	$ 75,872
Net income (loss)	(27,458)		852	2,357	(2,097)	5,006		1,259	5,129	3,104
Net income (loss) attributable to Reading International, Inc. common shareholders	$ (27,487)		$ 902	$ 2,394	$ (2,081)	$ 4,960		$ 1,297	$ 5,027	$ 3,082
Basic earnings (loss) per share	$ (0.99)		$ 0.04	$ 0.10	$ (0.09)	$ 0.21		$ 0.06	$ 0.22	$ 0.13
Diluted earnings (loss) per share	$ (0.99)		$ 0.04	$ 0.10	$ (0.09)	$ 0.21		$ 0.06	$ 0.22	$ 0.13
As Reported [Member] | Tax Year 2019 [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue												309,385	279,879
Operating income (loss)												24,078	20,706
Income (loss) before income taxes												17,918	34,492
Income tax benefit (expense)												(3,420)	(3,380)
Net income (loss)												14,498	31,112
Net income (loss) attributable to Reading International, Inc. common shareholders												$ 14,366	$ 31,101
Basic earnings (loss) per share												$ 0.62	$ 1.35
Diluted earnings (loss) per share												$ 0.62	$ 1.34
As Reported [Member] | Tax Year 2019 [Member] | Cinema [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue												$ 294,177	$ 263,464
Adjustments [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue			$ (70)	$ (87)	$ (58)	$ (113)		$ (111)	$ (137)	$ (93)
Net income (loss)			(51)	(63)	(43)	(80)		(82)	(101)	(69)
Net income (loss) attributable to Reading International, Inc. common shareholders			$ (51)	$ (63)	$ (43)	$ (80)		$ (82)	$ (101)	$ (69)
Adjustments [Member] | Tax Year 2019 [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue												(455)	(323)
Operating income (loss)												(455)	(323)
Income (loss) before income taxes												(455)	(323)
Income tax benefit (expense)												122	87
Net income (loss)												(332)	(236)
Net income (loss) attributable to Reading International, Inc. common shareholders												$ (332)	$ (236)
Basic earnings (loss) per share												$ (0.01)	$ (0.01)
Diluted earnings (loss) per share												$ (0.02)	$ (0.01)
Adjustments [Member] | Tax Year 2019 [Member] | Cinema [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue												$ (455)	$ (323)

[1] Since previously published financial statements have been corrected, there is no impact on the fourth quarter results for 2019 and so no data is displayed here.