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. Cash and cash equivalents at December 25, 2016 and December 27, 2015 were $69.1 million and $28.5 million, respectively and approximated their fair value.

Accounts receivable, net (in millions)

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



	December 25, 2016			December 27, 2015
Billed, current	$	102.8		$	96.6
Unbilled, current	128.3			112.0
Total current accounts receivable	231.1			208.6
Allowance for doubtful accounts	(1.7		)	(1.8		)
Total accounts receivable, net	$	229.4		$	206.8

Unbilled receivables represent the balance of recoverable costs and accrued profit, composed 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 $6.2 million as of December 25, 2016 and $6.4 million as of December 27, 2015 and are included in accounts receivable, net in the Consolidated Balance Sheets.

Substantially all accounts receivable at December 25, 2016, are expected to be collected in 2017. The Company does not believe it has significant exposure to credit risk, as accounts receivable and the related unbilled amounts are primarily from contracts where the end customer is the U.S. Government.

U.S. Government contract receivables where the Company is the prime contractor included in accounts receivable, net (in millions)



	December 25, 2016		December 27, 2015
Billed	$	15.6	$	13.5
Unbilled	39.3		31.0
Total U.S. Government contract receivables	$	54.9	$	44.5

Inventoried costs, net of progress payments (in millions)



	December 25, 2016			December 27, 2015
Raw materials	$	31.9		$	32.9
Work in process	22.1			19.2
Finished goods	1.4			2.6
Supplies and other	1.8			1.6
Subtotal inventoried costs	57.2			56.3
Less customer advances and progress payments	(1.8		)	(0.7		)
Total inventoried costs	$	55.4		$	55.6

Property and equipment, net (in millions)



	December 25, 2016			December 27, 2015
Land and buildings	$	12.2		$	13.3
Computer equipment and software	26.9			27.0
Machinery and equipment	47.2			47.4
Furniture and office equipment	5.3			5.8
Leasehold improvements	9.9			10.9
Construction in progress	6.1			5.7
Property and equipment	107.6			110.1
Accumulated depreciation and amortization	(57.8		)	(53.9		)
Total property and equipment, net	$	49.8		$	56.2

Depreciation expense was $12.3 million, $12.5 million and $13.3 million for the years ended December 25, 2016, December 27, 2015, and December 28, 2014, respectively.