Warranty Contracts (Tables)

12 Months Ended

Dec. 31, 2011

Warranty Contracts [Abstract]

Warranty Revenue Recognition

	Beginning Balance Deferred Warranty Revenue		Warranty Revenue Deferred		Warranty Revenue Recognized			Ending Balance Deferred Warranty Revenue
(in thousands)
Year Ended December 31,
2011	$	4,433	$	4,210	$	(5,549	)	$	3,094
2010		2,677		5,941		(4,185	)		4,433
2009		3,075		3,417		(3,815	)		2,677

Warranty Costs Incurred

(in thousands)	Materials		Labor and Overhead		Total
Year Ended December 31,
2011	$	2,020	$	3,565	$	5,585
2010		1,330		2,668		3,998
2009		1,288		2,476		3,764