Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 27, 2013	Dec. 31, 2012
Current Assets
Cash and cash equivalents	$ 53,690	$ 65,788
Accounts receivable, net of allowance of $823 and $374, respectively	58,829	42,652
Inventories	65,073	52,801
Income taxes receivable	3,906	16,540
Deferred tax assets	6,675	7,583
Prepaid expenses and other current assets	6,610	5,486
Assets of discontinued operations		17,618
Total current assets	194,783	208,468
Property, plant and equipment, net	32,702	32,338
Deferred tax assets	1,997	3,884
Other assets	9,074	8,172
Intangible assets, net	68,265	40,020
Goodwill	71,087	44,578
Total assets	377,908	337,460
Current Liabilities
Current portion of long-term debt	7,500	7,500
Accounts payable	27,100	18,824
Income taxes payable	2,983	3,317
Deferred revenue	947	316
Deferred tax liabilities	399	402
Accrued expenses and other current liabilities	22,334	18,962
Liabilities of discontinued operations	624	5,605
Total current liabilities	61,887	54,926
Long-term debt	70,875	42,500
Deferred tax liabilities	927	255
Income taxes payable	1,993	1,764
Other liabilities	8,958	9,809
Total liabilities	144,640	109,254
Commitments and Contingencies (Note 14)
Stockholders' Equity:
Common shares, no par value; Authorized shares: unlimited; Issued and outstanding: 33,959 and 33,796, respectively	423,856	423,856
Additional paid-in capital	25,157	21,924
Accumulated deficit	(205,221)	(208,222)
Accumulated other comprehensive loss	(10,963)	(9,749)
Total GSI Group Inc. stockholders' equity	232,829	227,809
Noncontrolling interest	439	397
Total stockholders' equity	233,268	228,206
Total liabilities and stockholders' equity	$ 377,908	$ 337,460