Deferred Revenue (Tables)

9 Months Ended

Sep. 30, 2012

Components of Deferred Revenue

The components of deferred revenue consist of the following (in thousands):

	September 30, 2012		December 31, 2011
Future service	$	27,324	$	25,809
Estimated potential penalties and holdbacks		9,889		8,510
	$	37,213	$	34,319