CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 33,285	$ 28,814
Short-term investments	3,590	12,340
Accounts receivable, net of allowances of $1,049 and $823 as of March 31, 2015 and December 31, 2014	18,787	17,864
Inventories	39,475	38,574
Related party notes receivable - current	173	171
Prepaid expenses and other current assets	4,312	5,430
Total current assets	99,622	103,193
Long-term investments	10,612	7,783
Property, plant and equipment, net	33,223	33,862
Related party notes receivable - long-term	1,710	1,704
Other assets	15,128	14,975
Total assets	160,295	161,517
Current liabilities:
Accounts payable	9,131	7,137
Accrued liabilities	5,815	7,634
Total current liabilities	14,946	14,771
Long-term portion of royalty payments	1,581	1,725
Other long-term liabilities	350	333
Total liabilities	16,877	16,829
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock, $0.001 par value; 2,000 shares authorized; 883 shares issued and outstanding as of March 31, 2015 and December 31, 2014 (Liquidation preference of $6.3 million and $6.3 million as of March 31, 2015 and December 31, 2014.)	3,532	3,532
Common stock, $0.001 par value; 70,000 shares authorized; 32,661 and 32,837 shares issued and outstanding as of March 31, 2015 and December 31, 2014.	32	32
Additional paid-in capital	195,152	195,419
Accumulated deficit	(69,417)	(68,393)
Accumulated other comprehensive income	7,620	7,673
Total AXT, Inc. stockholders' equity	136,919	138,263
Noncontrolling interests	6,499	6,425
Total stockholders' equity	143,418	144,688
Total liabilities and stockholders' equity	$ 160,295	$ 161,517