Income Taxes Schedule of Current and Deferred Tax Assets (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	$ 9,460,000	$ 6,808,000
Deferred Tax Assets, Operating Loss Carryforwards	6,106,000	11,898,000
Deferred Tax Assets, Inventory	5,381,000	4,532,000
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Warranty Reserves	4,024,000	3,111,000
Deferred Tax Assets, Deferred Income	3,958,000	2,915,000
Deferred Tax Asset Vacation Accrual	700,000	636,000
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Restructuring Charges	515,000	471,000
Deferred Tax Asset, Bad Debt Reserve	415,000	755,000
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Bonuses	36,000	40,000
Deferred Tax Assets, Other	0	725,000
Deferred Tax Assets, Gross	30,595,000	31,891,000
Deferred Tax Assets, Valuation Allowance	(2,551,000)	(4,990,000)
Deferred Tax Assets, Net of Valuation Allowance	28,044,000	26,901,000
Deferred Tax Liabilities, Property, Plant and Equipment	(14,789,000)	(20,829,000)
Deferred Tax Liabilities, Other	(750,000)	0
Deferred Tax Asset, Unrepatriated Earnings	0	(2,139,000)
Deferred Tax Liabilities, Net	(15,538,000)	(22,968,000)
Deferred Tax Assets, Net of Valuation Allowance, Current	19,477,000	9,014,000
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	13,998,000	1,642,000
Deferred Tax Assets, Net	$ 12,506,000	$ 3,933,000