Summary Of Significant Accounting Policies (Accounting Changes To Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Balance	$ 139,616	$ 179,979
Net income (loss)	(5,955)	(2,141)
Balance	117,400	179,334
Reading International Inc. Stockholders' Equity [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Balance	135,349	175,642
Net income (loss)	(5,875)	(2,125)
Balance	$ 113,231	175,067
Tax Year 2019 [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Balance		179,979
Net income (loss)		(2,141)
Balance		179,334
Tax Year 2019 [Member] | As Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Balance		180,547
Net income (loss)		(2,097)
Balance		179,946
Tax Year 2019 [Member] | Adjustments [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Balance		(568)
Net income (loss)		(44)
Balance		$ (612)