CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Current Assets
Cash and cash equivalents	$ 50,655	$ 56,781
Accounts receivable, net of allowance of $678 and $696, respectively	56,545	55,110
Income taxes receivable	21,975	21,920
Inventories	70,917	66,721
Deferred tax assets	4,242	4,226
Deferred cost of goods sold	1,703	7,789
Prepaid expenses and other current assets	5,657	5,580
Total current assets	211,694	218,127
Property, plant and equipment, net of accumulated depreciation of $59,924 and $55,336, respectively	42,489	45,402
Deferred tax assets	1,474	1,445
Other assets	5,624	4,476
Intangible assets, net	47,396	53,139
Goodwill	44,578	44,578
Total Assets	353,255	367,167
Current Liabilities
Accounts payable	22,003	19,766
Income taxes payable	2,819	1,785
Accrued compensation and benefits	9,085	7,988
Deferred revenue	4,126	15,006
Other accrued expenses	13,953	14,717
Total current liabilities	51,986	59,262
Debt	73,107	107,575
Deferred revenue	227	402
Deferred tax liabilities	8,477	8,373
Accrued restructuring, net of current portion	234	769
Income taxes payable	7,679	6,644
Accrued pension liability	2,467	3,044
Other liabilities	1,154	2,420
Total liabilities	145,331	188,489
Commitments and contingencies (Note 12)
Stockholders' Equity
Common shares, no par value; Authorized shares: unlimited; Issued and outstanding: 33,367,264 and 33,342,169 respectively	423,856	423,856
Additional paid-in capital	17,173	14,655
Accumulated deficit	(231,615)	(256,733)
Accumulated other comprehensive loss	(1,854)	(3,429)
Total GSI Group Inc. stockholders' equity	207,560	178,349
Noncontrolling interest	364	329
Total stockholders' equity	207,924	178,678
Total Liabilities and Stockholders' Equity	$ 353,255	$ 367,167