Certain Balance Sheet Components



Accounts receivable, net	September 30, 2011		December 31, 2010
	(in thousands)
Trade receivables (net of allowance of $7,452 and $9,045)	$	340,641	$	328,811
Unbilled receivables	36,466		42,851
Total accounts receivable, net	$	377,107	$	371,662

At September 30, 2011 and December 31, 2010, $887,000 and $12.5 million were recorded within trade receivables as billed but not yet paid by customers in accordance with contract retainage provisions. At September 30, 2011 and December 31, 2010, contract retainage amounts that were unbilled and classified as unbilled receivables were $5.8 million and $2.1 million. These contract retainage amounts within trade receivables and unbilled receivables are expected to be collected within the following 12 months.

At September 30, 2011 and December 31, 2010, long-term unbilled receivables and long-term retainage contract receivables totaled $31.4 million and $5.9 million. The net increase in long-term other assets from December 31, 2010 to September 30, 2011 includes $11.7 million of retainage contract receivables and $7.5 million of unbilled receivables, which were reclassified to long-term as of September 30, 2011 due to delays in reaching certain contract milestones required for payment. These long-term unbilled receivables and retainage contract receivables are classified within other long-term assets as collection is not anticipated within the following 12 months. However, collection is expected within the following 18 months.



Allowance for doubtful account activity	Three Months Ended September 30,						Nine Months Ended September 30,
	2011			2010			2011			2010
	(in thousands)
Beginning balance	$	8,980		$	6,298		$	9,045		$	6,339
Provision (release) of doubtful accounts, net	175			(904		)	128			(242		)
Accounts written-off	(1,127		)	(21		)	(1,680		)	(194		)
Effects of change in exchange rates	(576		)	393			(41		)	(137		)
Ending balance	$	7,452		$	5,766		$	7,452		$	5,766



Inventories	September 30, 2011		December 31, 2010
	(in thousands)
Materials	$	132,309	$	106,021
Work in process	17,209		18,389
Finished goods	91,047		83,747
Total inventories	$	240,565	$	208,157

Our inventory levels may vary period to period as a result of our factory scheduling and the timing of contract fulfillments, which may include the buildup of finished goods for shipment.

Consigned inventory is held at third-party locations; however, we retain title to the inventory until purchased by the third-party. Consigned inventory, consisting of raw materials and finished goods, was $14.5 million and $17.6 million at September 30, 2011 and December 31, 2010, respectively.



Property, plant, and equipment, net	September 30, 2011			December 31, 2010
	(in thousands)
Machinery and equipment	$	281,205		$	265,113
Computers and purchased software	75,657			63,077
Buildings, furniture, and improvements	146,841			146,661
Land	32,402			35,968
Construction in progress, including purchased equipment	20,104			20,531
Total cost	556,209			531,350
Accumulated depreciation	(268,644		)	(232,108		)
Property, plant, and equipment, net	$	287,565		$	299,242



Depreciation expense	Three Months Ended September 30,				Nine Months Ended September 30,
	2011		2010		2011		2010
	(in thousands)
Depreciation expense	$	16,607	$	15,231	$	49,112	$	45,725