CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current Assets
Cash and cash equivalents	$ 54,835	$ 56,781
Accounts receivable, net of allowance of $557 and $696, respectively	50,167	55,110
Income taxes receivable	22,707	21,920
Inventories	65,810	66,721
Deferred tax assets	5,335	4,226
Deferred cost of goods sold	1,998	7,789
Prepaid expenses and other current assets	5,969	5,580
Total current assets	206,821	218,127
Property, plant and equipment, net of accumulated depreciation	43,411	45,402
Deferred tax assets	814	1,445
Other assets	7,082	4,476
Intangible assets, net	45,797	53,139
Goodwill	44,578	44,578
Total assets	348,503	367,167
Current Liabilities
Short-term debt	10,000
Accounts payable	14,679	19,766
Income taxes payable	1,835	1,785
Accrued compensation and benefits	9,572	7,988
Deferred revenue	5,913	15,006
Deferred tax liabilities	140
Other accrued expenses	16,069	14,717
Total current liabilities	58,208	59,262
Long-term debt	58,000	107,575
Deferred revenue	152	402
Deferred tax liabilities	8,722	8,373
Income taxes payable	8,057	6,644
Accrued pension liabilities	4,265	3,044
Other liabilities	1,739	3,189
Total long-term liabilities	80,935	129,227
Total liabilities	139,143	188,489
Commitments and contingencies (Note 12)
Stockholders' Equity
Common shares, no par value; Authorized shares: unlimited; Issued and outstanding: 33,478 and 33,342, respectively	423,856	423,856
Additional paid-in capital	17,931	14,655
Accumulated deficit	(227,760)	(256,733)
Accumulated other comprehensive loss	(5,024)	(3,429)
Total GSI Group Inc. stockholders' equity	209,003	178,349
Noncontrolling interest	357	329
Total stockholders' equity	209,360	178,678
Total liabilities and stockholders' equity	$ 348,503	$ 367,167