CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) [Abstract]
Net loss	$ (899)us-gaap_ProfitLoss	$ (1,835)us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Change in foreign currency translation gain (loss), net of tax	238	(521)
Change in unrealized gain (loss) on available-for-sale investments, net of tax	(259)	(10)
Total other comprehensive loss, net of tax	(21)	(531)
Comprehensive loss	(920)	(2,366)
Less: Comprehensive income attributable to the noncontrolling interest	(157)	(126)
Comprehensive loss attributable to AXT, Inc.	$ (1,077)us-gaap_ComprehensiveIncomeNetOfTax	$ (2,492)us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of (increase) decrease in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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