Capital Stock and Reserves - Additional Information (Details) $ / shares in Units, $ / shares in Units, $ in Thousands, ¥ in Millions, $ in Millions	1 Months Ended	3 Months Ended				9 Months Ended				12 Months Ended
	Jun. 30, 2025 USD ($)	Sep. 30, 2025 USD ($) type $ / shares shares	Sep. 30, 2025 HKD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2024 HKD ($) $ / shares shares	Sep. 30, 2025 USD ($) type day $ / shares shares	Sep. 30, 2025 HKD ($) day $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2024 HKD ($) $ / shares shares	Dec. 31, 2024 shares	Sep. 30, 2025 CNY (¥) type shares	Jun. 12, 2025 shares	Jun. 07, 2024 shares	Jun. 30, 2020 USD ($)	Jun. 12, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $		$ 6,300		$ 5,400		$ 18,900		$ 16,900
Share-based compensation expense | $		$ 6,301		$ 5,399		$ 18,863		$ 16,938
Number of award grant types | type		2				2					2
Average closing price, number of days used in determining the grant date fair value | day						5	5
Common stock, shares issued (in shares)		53,798,934				53,798,934				52,946,200	53,798,934
Share repurchase program, authorized amount | $		$ 500,000				$ 500,000								$ 400,000	$ 200,000
Share repurchase program, extension period	12 months
Share repurchase program, increase in authorized, amount | $	$ 100,000	100,000				100,000
Remaining authorized amount for share repurchase program | $		$ 250,700				$ 250,700
Shares repurchased (in shares)		0	0	0	0	0	0	1,166,370	1,166,370
Average cost per share of stock repurchased (in dollars per share) | $ / shares								$ 13.99
Share repurchases during period | $								$ 16,300
Share purchases in the administration of employee-share plans (in shares)						0	0	0	0
Treasury shares held in trust for future settlement of share based awards (in shares)						0	0			0
Antidilutive securities excluded from the calculation of diluted weighted average shares outstanding (in shares)		844,551	844,551	2,192,874	2,192,874	928,945	928,945	2,769,499	2,769,499
Statutory surplus reserve		$ 4,200				$ 4,200					¥ 37.7
Statutory surplus reserve to its subsidiaries registered capital (as a percent)		50.00%				50.00%					50.00%
IMAX China
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchased (in shares)		0	0	0	0	1,495,900	1,495,900	119,900	119,900
Average cost per share of stock repurchased (in dollars per share) | (per share)		$ 0.96	$ 7.56	$ 0.95	$ 7.43	$ 0.96	$ 7.56	$ 0.95	$ 7.43
Share repurchases during period		$ 1,400	$ 11.3	$ 100	$ 0.9	$ 1,400	$ 11.3	$ 100	$ 0.9
Share repurchase program, maximum shares authorized to be purchases (as a percent)												10.00%	10.00%
Share repurchase program, authorized shares (in shares)												33,919,122	34,000,845
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $		$ 3,812		$ 3,111		$ 11,198		$ 9,986
Antidilutive securities excluded from the calculation of diluted weighted average shares outstanding (in shares)		0	0	0	0	0	0	10,798	10,798
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $		$ 2,057		$ 2,048		$ 5,958		$ 5,866
Share-based awards vesting period						3 years	3 years
Antidilutive securities excluded from the calculation of diluted weighted average shares outstanding (in shares)		1,510	1,510	0	0	85,904	85,904	42,848	42,848
Performance Shares | Award Year 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting percentage						150.00%	150.00%
Performance Shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting percentage						175.00%	175.00%
Performance Shares | Maximum | EBITDA
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued (in shares)		1,940,472				1,940,472					1,940,472
Performance Shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting percentage						0.00%	0.00%
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from the calculation of diluted weighted average shares outstanding (in shares)		843,041	843,041	2,192,874	2,192,874	843,041	843,041	2,715,853	2,715,853
Non-Employees | Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $		$ 100		$ 100		$ 1,700		$ 1,800
Value of shares granted in period that vested immediately | $						$ 1,700