Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2012

Accounting Policies [Abstract]

Activity in Warranty Accrual

The following table provides the activity in the warranty accrual:

	Three Months Ended			Three Months Ended			Six Months Ended			Six Months Ended
	June 30, 2012			June 30, 2011			June 30, 2012			June 30, 2011
Balance at beginning of period	$	4,733		$	3,700		$	4,600		$	3,200
Charged to expense	1,126			1,015			2,227			2,630
Warranty payments	(1,099		)	(673		)	(2,067		)	(1,788		)
Balance at end of period	$	4,760		$	4,042		$	4,760		$	4,042