Accrued Product Warrenties Accrued Product Warrenties (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrued product warranties, beginning of period			$ 16,152	$ 16,046	$ 16,791		$ 15,322
Amounts paid for warranty services	(1,128)	(2,465)	(5,273)	(6,722)
Warranty provisions for products sold	768	1,689	5,309	4,823
Currency translation adjustments and other	160	646	403	1,045
Accrued product warranties, end of period	16,591	15,192	16,591	15,192	16,791		15,322
Current accrued product warranties, end of period	13,464	13,094	13,464	13,094		13,169
Long-term accrued product warranties, end of period	$ 3,127	$ 2,098	$ 3,127	$ 2,098