Valuation and Qualifying Accounts (Schedule) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for doubtful accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 1,198	$ 845	$ 5,674
Disposed Reserves During the Period			(4,273)
Charged (Credited) to Costs and Expenses	5,811	597	1,689
Deductions	(298)	(244)	(2,245)
Balance at End of Year	6,711	1,198	845
Allowance for doubtful notes [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year			71
Disposed Reserves During the Period			(71)
Charged (Credited) to Costs and Expenses			0
Deductions			0
Balance at End of Year			0
Warranty [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	715	784	5,088
Disposed Reserves During the Period			(3,821)
Charged (Credited) to Costs and Expenses	1,258	1,165	443
Deductions	(932)	(1,234)	(926)
Balance at End of Year	1,041	715	784
Valuation allowance on deferred tax assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	69,475	62,700	33,126
Disposed Reserves During the Period			(15,897)
Charged (Credited) to Costs and Expenses	(6,214)	6,775	45,471
Deductions	0	0	0
Balance at End of Year	63,261	69,475	62,700
Excess and obsolete inventory [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	13,037	12,876	30,618
Disposed Reserves During the Period			(15,819)
Charged (Credited) to Costs and Expenses	1,326	567	1,587
Deductions	(124)	(406)	(3,510)
Balance at End of Year	$ 14,239	$ 13,037	$ 12,876