Certain Balance Sheet Components



Accounts receivable, net	June 30, 2011		December 31, 2010
	(in thousands)
Trade receivables (net of allowance of $8,980 and $9,045)	$	348,736	$	328,811
Unbilled receivables	29,099		42,851
Total accounts receivable, net	$	377,835	$	371,662

At June 30, 2011 and December 31, 2010, $134,000 and $12.5 million were recorded within trade receivables as billed but not yet paid by customers in accordance with contract retainage provisions. At June 30, 2011 and December 31, 2010, contract retainage amounts that were unbilled and classified as unbilled receivables were $4.5 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 June 30, 2011 and December 31, 2010, long-term unbilled receivables and long-term retainage contract receivables were $36.5 million and $5.9 million. The increase in long-term receivables from December 31, 2010 to June 30, 2011 includes $12.5 million of retainage contract receivables and $12.0 million of unbilled receivables, which were reclassified to long-term at June 30, 2011 due to a delay 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 June 30,						Six Months Ended June 30,
	2011			2010			2011			2010
	(in thousands)
Beginning balance	$	9,030		$	5,870		$	9,045		$	6,339
Provision (release) of doubtful accounts, net	298			742			(48		)	662
Accounts written-off	(505		)	(43		)	(552		)	(173		)
Effects of change in exchange rates	157			(271		)	535			(530		)
Ending balance	$	8,980		$	6,298		$	8,980		$	6,298



Inventories	June 30, 2011		December 31, 2010
	(in thousands)
Materials	$	132,303	$	106,021
Work in process	26,058		18,389
Finished goods	94,718		83,747
Total inventories	$	253,079	$	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 $15.1 million and $17.6 million at June 30, 2011 and December 31, 2010, respectively.



Property, plant, and equipment, net	June 30, 2011			December 31, 2010
	(in thousands)
Machinery and equipment	$	284,431		$	265,113
Computers and purchased software	69,894			63,077
Buildings, furniture, and improvements	150,987			146,661
Land	33,879			35,968
Construction in progress, including purchased equipment	24,600			20,531
Total cost	563,791			531,350
Accumulated depreciation	(262,333		)	(232,108		)
Property, plant, and equipment, net	$	301,458		$	299,242