Unaudited Quarterly Consolidated Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Unaudited Quarterly Consolidated Financial Data
Revenue	$ 18,057	$ 18,371	$ 21,010	$ 20,064	$ 19,567	$ 23,138	$ 21,449	$ 19,345	$ 77,502	$ 83,499	$ 85,335
Gross Profit	3,090	4,605	4,385	4,749	4,971	5,318	4,160	2,718	16,829	17,167	11,828
Net Income (Loss) Attributable to Parent	$ (1,243)	$ 42	$ (3)	$ (1,024)	$ (311)	$ 644	$ 319	$ (2,040)	$ (2,228)	$ (1,388)	$ (7,958)
Net (loss) attributable to AXT, Inc per share, basic (in dollar per share)	$ (0.04)	$ 0.00	$ 0.00	$ (0.03)	$ (0.01)	$ 0.02	$ 0.01	$ (0.06)	$ (0.07)	$ (0.05)	$ (0.25)
Net (loss) attributable to AXT, Inc per share, diluted (in dollar per share)	$ (0.04)	$ 0.00	$ 0.00	$ (0.03)	$ (0.01)	$ 0.02	$ 0.01	$ (0.06)	$ (0.07)	$ (0.05)	$ (0.25)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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