CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands	Jul. 01, 2011	Dec. 31, 2010
Current Assets
Cash and cash equivalents	$ 73,999	$ 56,781
Accounts receivable, net of allowance of $563 and $696, respectively	58,339	55,110
Income taxes receivable	21,984	21,920
Inventories	71,112	66,721
Deferred tax assets	4,319	4,226
Deferred cost of goods sold	3,138	7,789
Prepaid expenses and other current assets	6,125	5,580
Total current assets	239,016	218,127
Property, plant and equipment, net of accumulated depreciation of $59,379 and $55,336, respectively	43,623	45,402
Deferred tax assets	1,729	1,445
Other assets	5,799	4,476
Intangible assets, net	49,269	53,139
Goodwill	44,578	44,578
Total Assets	384,014	367,167
Current Liabilities
Accounts payable	19,465	19,766
Income taxes payable	2,835	1,785
Accrued compensation and benefits	10,939	7,988
Deferred revenue	7,195	15,006
Deferred tax liabilities	11
Other accrued expenses	14,782	14,717
Total current liabilities	55,227	59,262
Debt	108,107	107,575
Deferred revenue	360	402
Deferred tax liabilities	8,486	8,373
Accrued restructuring, net of current portion	471	769
Income taxes payable	7,275	6,644
Accrued pension liability	2,663	3,044
Other liabilities	1,490	2,420
Commitments and contingencies (Note 12)
Stockholders' Equity:
Common shares, no par value; Authorized shares: unlimited; Issued and outstanding: 33,352,192 and 33,342,169 respectively	423,856	423,856
Additional paid-in capital	16,415	14,655
Accumulated deficit	(240,460)	(256,733)
Accumulated other comprehensive loss	(269)	(3,429)
Total GSI Group Inc. stockholders' equity	199,542	178,349
Noncontrolling interest	393	329
Total stockholders' equity	199,935	178,678
Total Liabilities and Stockholders' Equity	$ 384,014	$ 367,167