Basis of Presentation (Details)		1 Months Ended								3 Months Ended			6 Months Ended	12 Months Ended
	Jan. 25, 2021 USD ($)	Aug. 31, 2022 USD ($)	May 31, 2022 USD ($)	Apr. 30, 2022 USD ($)	Jan. 31, 2022 USD ($)	Jun. 30, 2021 USD ($)	May 31, 2021 USD ($)	Feb. 28, 2021 USD ($)	Jan. 31, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($) company	Dec. 31, 2021 USD ($) company	Dec. 31, 2020 USD ($)	Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Nov. 30, 2020	May 31, 2019	Apr. 30, 2019
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of equity method investments | company													5	5
Investments, equity method										$ 13,082,000			$ 13,082,000	$ 10,166,000
Investment in subsidiary with noncontrolling interest		$ 334,000								$ 1,179,000	$ 575,000	$ 576,000
AXT-Tongmei, Inc | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash consideration						$ 1,000,000					$ 1,000,000
ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd | Loan from related party
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Investment in subsidiary with noncontrolling interest				$ 4,500,000
Increase in redeemable noncontrolling interests			$ 100,000
ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd | Loan from related party | ChaoYang Xinshuo
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Loan amount																$ 1,000,000.0	$ 900,000
Investment in subsidiary with noncontrolling interest				1,900,000
Amount paid to subsidiary			600,000	700,000
ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd | Loan from related party | Beijing Tongmei Xtal Technology
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Investment in subsidiary with noncontrolling interest				2,600,000
Amount paid to subsidiary			$ 800,000	$ 1,100,000
Increase in noncontrolling interest					$ 2,200,000
Increase in redeemable noncontrolling interests					$ 200,000
ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Investment value, agreement amount							$ 1,800,000	$ 3,000,000.0
Investments, equity method								$ 1,800,000
Ownership (as a percent)			58.50%	58.50%	58.50%		58.50%	58.50%
Initial funding							$ 1,500,000	$ 1,500,000
ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Investment value, agreement amount				$ 4,400,000
Investments, equity method				$ 3,300,000
Ownership (as a percent)				75.00%
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage of outstanding shares															33.00%
Percentage of ownership															67.00%			63.00%
Beijing Tongmei Xtal Technology
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage of outstanding shares	7.28%									14.50%			14.50%
Private equity ownership percentage	7.28%												14.50%
Percentage of key managers and contributors purchased															0.40%
Investment in new facility	$ 49,000,000														$ 48,100,000
Raised additional capital									$ 1,500,000
Percentage of ownership						85.50%					85.50%
Transaction results in increase to noncontrolling interests						$ 1,200,000
Transaction results in increase to redeemable noncontrolling interests						$ 1,200,000
Increase in redeemable noncontrolling interests									$ 1,500,000						$ 48,100,000
Beijing Tongmei Xtal Technology | Beijing Boyu Semiconductor Vessel Craftwork Technology Co Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Private equity ownership percentage															7.59%
Beijing Tongmei Xtal Technology | Nanjing JinMei Gallium Co., Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Private equity ownership percentage															0.38%
Beijing Tongmei Xtal Technology | ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Loan amount					$ 1,400,000									$ 1,400,000
Beijing Tongmei Xtal Technology | ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd | Loan from related party
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Increase in noncontrolling interest			$ 1,400,000
Beijing Tongmei Xtal Technology | ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Investment amount							$ 900,000	$ 900,000
Nanjing JinMei Gallium Co., Ltd Investment
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage of outstanding shares															8.50%
Percentage of ownership																			100.00%	97.00%
Nanjing JinMei Gallium Co., Ltd Investment | Nanjing JinMei Gallium Co., Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Private equity ownership percentage															0.38%