Inventories (Tables)

3 Months Ended

Mar. 31, 2013

Inventory Disclosure [Abstract]

Components of inventory

The components of inventories consist of the following (in thousands):

	December 31, 2012		March 31, 2013
Purchased parts and materials	$	3,051	$	3,277
Finished goods	1,986		1,667
Total inventory	$	5,037	$	4,944