CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	AXT, Inc. Stockholders' Equity	Noncontrolling Interests	Total
Balance, beginning of period at Dec. 31, 2020	$ 3,532	$ 42	$ 230,381	$ (44,545)	$ 3,209	$ 192,619	$ 15,350	$ 207,969
Balance (in shares) at Dec. 31, 2020	883	41,967
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised		$ 1	1,669			1,670		1,670
Common stock options exercised (in shares)		507
Formation of new subsidiary with noncontrolling interests			(262)			(262)	1,413	1,151
Transfer of subsidiary with noncontrolling interests			(1,229)			(1,229)	1,229
Restricted stock awards canceled		(14)
Stock-based compensation			4,519			4,519		4,519
Issuance of common stock in the form of restricted stock (in shares)		426
Purchase of subsidiary shares from noncontrolling interests			(2,691)			(2,691)	(1,039)	(3,730)
Transfer of subsidiary with redeemable noncontrolling interest			(1,241)			(1,241)		(1,241)
Noncontrolling interest portion of Tongmei stock-based compensation			(62)			(62)	40	(22)
Sale of common stock to employees in connection with the reorganization			538			538		538
Net income (loss)				14,575		14,575	1,045	15,620
Other comprehensive income (loss)					3,093	3,093	279	3,372
Balance, end of period at Dec. 31, 2021	$ 3,532	$ 43	231,622	(29,970)	6,302	211,529	18,317	229,846
Balance (in shares) at Dec. 31, 2021	883	42,886
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised		$ 1	517			518		518
Common stock options exercised (in shares)		172
Restricted stock awards canceled		(91)
Stock-based compensation			3,273			3,273		3,273
Issuance of common stock in the form of restricted stock (in shares)		587
Purchase of subsidiary shares from noncontrolling interests			(466)			(466)	2,699	2,233
Noncontrolling interest portion of Tongmei stock-based compensation			100			100	(42)	58
Net income (loss)				15,811		15,811	1,333	17,144
Other comprehensive income (loss)					(9,420)	(9,420)	(901)	(10,321)
Investment in subsidiary from noncontrolling interest							1,887	1,887
Investment in subsidiary with redeemable noncontrolling interest			(471)			(471)		(471)
Tongmei stock-based compensation			733			733		733
Balance, end of period at Dec. 31, 2022	$ 3,532	$ 44	235,308	(14,159)	(3,118)	221,607	23,293	244,900
Balance (in shares) at Dec. 31, 2022	883	43,554
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised			10			10		10
Common stock options exercised (in shares)		4
Restricted stock awards canceled		(23)
Stock-based compensation			2,779			2,779		2,779
Issuance of common stock in the form of restricted stock (in shares)		704
Purchase of subsidiary shares from noncontrolling interests			(153)			(153)	861	708
Noncontrolling interest portion of Tongmei stock-based compensation			(98)			(98)	55	(43)
Net income (loss)				(17,881)		(17,881)	(391)	(18,272)
Other comprehensive income (loss)					(2,881)	(2,881)	(324)	(3,205)
Investment in subsidiary with redeemable noncontrolling interest			(155)			(155)		(155)
Tongmei stock-based compensation			761			761		761
Balance, end of period at Dec. 31, 2023	$ 3,532	$ 44	$ 238,452	$ (32,040)	$ (5,999)	$ 203,989	$ 23,494	$ 227,483
Balance (in shares) at Dec. 31, 2023	883	44,239