Balance Sheet Details

The detail of certain assets in the Consolidated Balance Sheets consists of the following (in millions).

Cash and cash equivalents

The Company's cash equivalents consist of overnight cash sweep accounts that are invested on a daily basis. The cash and cash equivalents at December 25, 2011 and December 30, 2012 were as follows:



	December 25, 2011				December 30, 2012
	Amortized Cost Basis		Level 1 Fair Value Basis		Amortized Cost Basis		Level 1 Fair Value Basis
Cash and cash equivalents	$	69.6	$	69.6	$	49.0	$	49.0

Net unrealized and realized gains recorded during the years ended December 25, 2011 and December 30, 2012 were immaterial.

Accounts receivable, net

Receivables including amounts due under long-term contracts are summarized as follows:



	December 25, 2011			December 30, 2012
Billed, current	$	128.7		$	137.9
Unbilled, current	118.6			135.4
Total current accounts receivable	247.3			273.3
Allowance for doubtful accounts	(2.0		)	(1.4		)
Total current accounts receivable, net	245.3			271.9
Unbilled, long-term (included in other assets)	0.3			0.3
Total accounts receivable, net	$	245.6		$	272.2

Unbilled receivables represent the balance of recoverable costs and accrued profit, comprised principally of revenue recognized on contracts for which billings have not been presented to the customer because the amounts were earned but not contractually billable as of the balance sheet date. Retainages receivable were $3.9 million as of December 25, 2011 and $3.5 million as of December 30, 2012 and are included in accounts receivable, net in the Consolidated Balance Sheets.

U.S. Government contract receivables (included in accounts receivable, net)



	December 25, 2011		December 30, 2012
Billed	$	41.2	$	24.6
Unbilled	43.3		39.4
Total U.S. Government contract receivables	$	84.5	$	64.0

Inventoried costs, net of progress payments



	December 25, 2011			December 30, 2012
Raw materials	$	43.3		$	48.4
Work in process	25.7			36.5
Finished goods	6.9			7.3
Supplies and other	4.0			2.2
Subtotal inventoried costs	79.9			94.4
Less customer advances and progress payments	(3.3		)	(0.1		)
Total inventoried costs	$	76.6		$	94.3

Property and equipment, net



	December 25, 2011			December 30, 2012
Land and buildings	$	20.6		$	20.8
Computer equipment and software	17.8			17.2
Machinery and equipment	37.5			49.9
Furniture and office equipment	8.3			12.2
Facility under capital lease	1.0			1.6
Leasehold improvements	8.2			13.3
Construction in progress	1.7			5.8
Property and equipment	95.1			120.8
Accumulated depreciation and amortization	(22.6		)	(35.2		)
Total property and equipment, net	$	72.5		$	85.6

Depreciation expense was $3.7 million, $10.0 million and $14.1 million for the years ended December 26, 2010, December 25, 2011, and December 30, 2012, respectively.