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, 2019	$ 3,532	$ 41	$ 236,957	$ (47,783)	$ (4,862)	$ 187,885	$ 4,877	$ 192,762
Balance (in shares) at Dec. 31, 2019	883	40,632
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised		$ 1	2,535			2,536		2,536
Common stock options exercised (in shares)		905
Sale of subsidiary shares to noncontrolling interests			396			396		396
Restricted stock awards canceled		(13)
Stock-based compensation			2,623			2,623		2,623
Issuance of common stock in the form of restricted stock (in shares)		443
Purchase of subsidiary shares from noncontrolling interests			(1,398)			(1,398)	(202)	(1,600)
Adjustment to noncontrolling interests in connection with the reorganization and alignment of assets under Tongmei			(10,732)			(10,732)	10,732
Net dividend declared by joint ventures							(2,238)	(2,238)
Net income				3,238		3,238	1,803	5,041
Other comprehensive income (loss)					8,071	8,071	378	8,449
Balance, end 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
Sale of subsidiary shares to noncontrolling interests			(262)			(262)	1,413	1,151
Transfer of subsidiary with noncontrolling interests			(1,229)			(1,229)	1,229
Investment in subsidiary with redeemable noncontrolling interest								(132)
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
Adjustment to noncontrolling interests in connection with the reorganization and alignment of assets under Tongmei								(1,229)
Net income				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
Tongmei stock-based compensation			733			733		733
Investment in subsidiary from noncontrolling interest							1,887	1,887
Investment in subsidiary with redeemable noncontrolling interest			(471)			(471)		(471)
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				15,811		15,811	1,333	17,144
Other comprehensive income (loss)					(9,420)	(9,420)	(901)	(10,321)
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