Commitments and Contingencies - (Tables)

3 Months Ended

Mar. 31, 2013

Commitments and Contingencies [Abstract]

Schedule of changes product warranty liability [Table Text Block]

Changes in the Company’s warranty reserves are as follows:

	Three Months Ended March 31,
	2013			2012
Balance, beginning of the period	$	2,024		$	1,406
Accruals	446			506
Usage	(705		)	(522		)
Balance, end of the period	$	1,765		$	1,390