Earnings Per Share (Tables)	9 Months Ended
Sep. 30, 2021
Earnings Per Share [Abstract]
Computation Of Basic And Diluted Earnings (Loss) Per Share	Quarter Ended Nine Months Ended September 30, September 30,(Dollars in thousands, except share data) 2021 2020 2021 2020Numerator: Net income (loss) attributable to Reading International, Inc $ (10,095) (19,228) $ 31,572 $ (47,806)Denominator: Weighted average number of common stock – basic 21,809,402 21,748,531 21,792,007 21,749,146Weighted average dilutive impact of awards — — 670,650 —Weighted average number of common stock – diluted 21,809,402 21,748,531 22,462,657 21,749,146Basic earnings (loss) per share $ (0.46) (0.88) $ 1.45 $ (2.20)Diluted earnings (loss) per share $ (0.46) (0.88) $ 1.41 $ (2.20)Awards excluded from diluted earnings (loss) per share 492,344 674,676 517,344 674,676

Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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