Restructuring (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restructuring Cost and Reserve
Restructuring expenses	$ 595	$ 562	$ 1,058	$ 3,508	$ 2,215	$ 3,508	$ 2,224
Components of restructuring expenses and reserve
Accrued restructuring, beginning of period					2,366	1,324
Employee severance, benefits and related costs					1,624	3,697
Payments					(2,674)	(2,523)
Inventory and other adjustments					67	(132)
Accrued restructuring, end of period	1,383			2,366	1,383	2,366	1,324
Employee severance and benefits
Restructuring Cost and Reserve
Restructuring expenses					1,500	3,500
Manufacturing facility divestiture
Restructuring Cost and Reserve
Restructuring expenses					$ 700