This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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- Definition

Amount after tax and 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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- Definition

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

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- Definition

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

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- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

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No definition available.

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- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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- Definition

Number of share options (or share units) exercised during the current period.

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Value of stock issued as a result of the exercise of stock options.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Preferred Stock [Member]	Common Stock [Member]	Additional Paid In Capital [Member]	Accumulated Deficit [Member]	Other Comprehensive Income/(Loss) [Member]	AXT, Inc. stockholders' equity [Member]	Noncontrolling interests [Member]	Total
Balance at Dec. 31, 2011	$ 3,532	$ 32	$ 191,554	$ (62,157)	$ 5,818	$ 138,779	$ 8,270	$ 147,049
Balance (in shares) at Dec. 31, 2011	883	32,222
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised			294			294		294
Common stock options exercised (in shares)		136
Stock-based compensation			1,215			1,215		1,215
Issuance of common stock in the form of restricted stock (in shares)		113
Comprehensive income:
Net Income (loss)				3,110		3,110	3,040	6,150us-gaap_ProfitLoss
Net dividend declared by joint ventures							(4,086)	(4,086)
Change in unrealized (loss) gain on marketable securities					85	85		85
Currency translation adjustment					130	130	77	207
Balance at Dec. 31, 2012	3,532	32	193,063	(59,047)	6,033	143,613	7,301	150,914
Balance (in shares) at Dec. 31, 2012	883	32,471
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised			532			532		532
Common stock options exercised (in shares)		331
Common stock repurchased			(716)			(716)		(716)
Common stock repurchased (in shares)		(285)
Stock-based compensation			1,277			1,277		1,277
Issuance of common stock in the form of restricted stock (in shares)		88
Comprehensive income:
Net Income (loss)				(7,958)		(7,958)	1,145	(6,813)us-gaap_ProfitLoss
Net dividend declared by joint ventures							(2,898)	(2,898)
Change in unrealized (loss) gain on marketable securities					1,682	1,682		1,682
Currency translation adjustment					1,238	1,238	330	1,568
Balance at Dec. 31, 2013	3,532	32	194,156	(67,005)	8,953	139,668	5,878	145,546
Balance (in shares) at Dec. 31, 2013	883	32,605
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock options exercised			134			134		134
Common stock options exercised (in shares)		111
Stock-based compensation			1,129			1,129		1,129
Issuance of common stock in the form of restricted stock (in shares)		121
Comprehensive income:
Net Income (loss)				(1,388)		(1,388)	691	(697)us-gaap_ProfitLoss
Net dividend declared by joint ventures							(83)	(83)
Change in unrealized (loss) gain on marketable securities					(964)	(964)		(964)
Currency translation adjustment					(316)	(316)	(61)	(377)
Balance at Dec. 31, 2014	$ 3,532	$ 32	$ 195,419	$ (68,393)	$ 7,673	$ (138,263)	$ (6,425)	$ 144,688
Balance (in shares) at Dec. 31, 2014	883	32,837