Restatement of Previously Issued Fiancial Statements Restatement of Previously Issued Financial Statements (Quarterly Consolidated Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010
Liabilities and Equity	$ 174,039	$ 154,746
Stockholders' Equity Attributable to Parent	119,603	101,044
Accumulated Other Comprehensive Income (Loss), Net of Tax	10,619	10,630
Retained Earnings (Accumulated Deficit)	(161,000)	(165,308)
Additional Paid in Capital	267,069	252,907
Common Stock, Value, Issued	2,915	2,815
Commitments and Contingencies
Liabilities	54,436	53,702
Other Liabilities, Noncurrent	699	3,028
Long-term Debt, Excluding Current Maturities	25	68
Deferred Tax Liabilities, Net, Noncurrent	962	933
Liabilities, Current	52,750	49,673
Deferred Tax Liabilities, Net, Current	499	499
Debt, Current	9,844	5,431
Deferred revenue	5,149	1,042
Employee-related Liabilities, Current	5,025	6,343
Accrued warranty	244	258
Accounts Payable and Accrued Liabilities, Current	31,989	36,100
Assets	174,039	154,746
Other Assets, Noncurrent	38	200
Defined Benefit Plan, Funded Status of Plan	6,945	6,359
Goodwill	24,826	24,887
Intangible Assets, Net (Excluding Goodwill)	758	1,111
Property, Plant and Equipment, Net	35,806	28,541
Assets, Current	105,666	93,648
Prepaid Expense and Other Assets, Current	2,975	3,152
Inventory, Net	43,802	33,234
Accounts Receivable, Net, Current	38,816	27,973
Cash and cash equivalents, end of period	20,073	29,289	30,988	39,829
Debt Classification Adjustments [Member]
Liabilities and Equity	0	0
Stockholders' Equity Attributable to Parent	0	0
Accumulated Other Comprehensive Income (Loss), Net of Tax	0	0
Retained Earnings (Accumulated Deficit)	0	0
Additional Paid in Capital	0	0
Common Stock, Value, Issued	0	0
Liabilities	0	0
Other Liabilities, Noncurrent	0	0
Long-term Debt, Excluding Current Maturities	(2,935)	0
Deferred Tax Liabilities, Net, Noncurrent	0	0
Liabilities, Current	2,935	0
Deferred Tax Liabilities, Net, Current	0	0
Debt, Current	2,935	0
Deferred revenue	0	0
Employee-related Liabilities, Current	0	0
Accrued warranty	0	0
Accounts Payable and Accrued Liabilities, Current	0	0
Assets	0	0
Other Assets, Noncurrent	(41)	(61)
Defined Benefit Plan, Funded Status of Plan	0	0
Goodwill	0	0
Intangible Assets, Net (Excluding Goodwill)	0	0
Property, Plant and Equipment, Net	0	0
Assets, Current	41	61
Prepaid Expense and Other Assets, Current	41	61
Inventory, Net	0	0
Accounts Receivable, Net, Current	0	0
Cash and cash equivalents, end of period	0	0
Restatement Adjustment [Member]
Liabilities and Equity	(2,195)	(2,190)
Stockholders' Equity Attributable to Parent	(6,544)	(2,287)
Accumulated Other Comprehensive Income (Loss), Net of Tax	0	0
Retained Earnings (Accumulated Deficit)	(6,544)	(2,287)
Additional Paid in Capital	0	0
Common Stock, Value, Issued	0	0
Liabilities	4,349	97
Other Liabilities, Noncurrent	0	0
Long-term Debt, Excluding Current Maturities	0	0
Deferred Tax Liabilities, Net, Noncurrent	0	0
Liabilities, Current	4,349	97
Deferred Tax Liabilities, Net, Current	0	0
Debt, Current	0	0
Deferred revenue	5,149	0
Employee-related Liabilities, Current	0	100
Accrued warranty	0	0
Accounts Payable and Accrued Liabilities, Current	(800)	(3)
Assets	(2,195)	(2,190)
Other Assets, Noncurrent	0	0
Defined Benefit Plan, Funded Status of Plan	0	0
Goodwill	0	0
Intangible Assets, Net (Excluding Goodwill)	0	0
Property, Plant and Equipment, Net	0	0
Assets, Current	(2,195)	(2,190)
Prepaid Expense and Other Assets, Current	105	(34)
Inventory, Net	11,872	6,002
Accounts Receivable, Net, Current	(14,172)	(8,158)
Cash and cash equivalents, end of period	0	0	0
Scenario, Previously Reported [Member]
Liabilities and Equity	176,234	156,936
Stockholders' Equity Attributable to Parent	126,147	103,331
Accumulated Other Comprehensive Income (Loss), Net of Tax	10,619	10,630
Retained Earnings (Accumulated Deficit)	(154,456)	(163,021)
Additional Paid in Capital	267,069	252,907
Common Stock, Value, Issued	2,915	2,815
Liabilities	50,087	53,605
Other Liabilities, Noncurrent	699	3,028
Long-term Debt, Excluding Current Maturities	2,960	68
Deferred Tax Liabilities, Net, Noncurrent	962	933
Liabilities, Current	45,466	49,576
Deferred Tax Liabilities, Net, Current	499	499
Debt, Current	6,909	5,431
Deferred revenue	0	1,042
Employee-related Liabilities, Current	5,025	6,243
Accrued warranty	244	258
Accounts Payable and Accrued Liabilities, Current	32,789	36,103
Assets	176,234	156,936
Other Assets, Noncurrent	79	261
Defined Benefit Plan, Funded Status of Plan	6,945	6,359
Goodwill	24,826	24,887
Intangible Assets, Net (Excluding Goodwill)	758	1,111
Property, Plant and Equipment, Net	35,806	28,541
Assets, Current	107,820	95,777
Prepaid Expense and Other Assets, Current	2,829	3,125
Inventory, Net	31,930	27,232
Accounts Receivable, Net, Current	52,988	36,131
Cash and cash equivalents, end of period	$ 20,073	$ 29,289	$ 30,988	$ 39,829