Receivables

The following table presents the components of "Receivables" appearing in the accompanying Consolidated Balance Sheets at December 28, 2012 and September 28, 2012 as well as certain other related information (in thousands):



	December 28, 2012		September 28, 2012
Components of receivables:
Amounts billed	$	1,119,114	$	1,193,500
Unbilled receivables and other	1,060,652		1,110,008
Retentions receivable	44,093		45,384
Total receivables, net	$	2,223,859	$	2,348,892
Other information about receivables:
Amounts due from the United States federal government, included above, net of advanced billings	$	261,272	$	294,327
Claims receivable	$	32,737	$	26,309

Billed receivables consist of amounts invoiced to clients in accordance with the terms of our client contracts and are shown net of an allowance for doubtful accounts. We anticipate that substantially all of such billed amounts will be collected over the next twelve months.

Unbilled receivables and retentions receivable represent reimbursable costs and amounts earned and reimbursable under contracts in progress as of the respective balance sheet dates. Such amounts become billable according to the contract terms, which usually consider the passage of time, achievement of certain milestones or completion of the project. We anticipate that substantially all of such unbilled amounts will be billed and collected over the next twelve months.

Claims receivable are included in "Receivables" in the accompanying Consolidated Balance Sheets and represent certain costs incurred on contracts to the extent it is probable that such claims will result in additional contract revenue and the amount of such additional revenue can be reliably estimated.