Description Of Business And Summary Of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2011

Description Of Business And Summary Of Significant Accounting Policies [Abstract]

Changes In Warranty Obligation

	December 31,
	2011			2010
Balance at beginning of year	$	9,569		$	9,447
Accruals for warranties issued during the year		24,612			19,683
Actual warranty claims received during the year		(22,295	)		(19,561	)
Balance at end of year	$	11,886		$	9,569

Changes In Deferred Maintenance Revenue

	December 31,
	2011			2010
Balance at beginning of year	$	146,840		$	109,538
Additions to deferred maintenance revenue		313,364			212,062
Amortization of deferred maintenance revenue		(243,177	)		(174,760	)
Balance at end of year	$	217,027		$	146,840

Components Of Foreign Currency Translation Adjustments

	2011		2010			2009
Beginning balance	$	1,602	$	4,740		$	3,935
Foreign currency translation adjustments		239		(3,138	)		805
Ending balance	$	1,841	$	1,602		$	4,740