Accounts Receivable

12 Months Ended

Dec. 31, 2017

Accounts Receivable, Net [Abstract]

Accounts Receivable

Accounts Receivable, net

Accounts receivable at December 31 consisted of the following:

	2017			2016
U.S. government contracts		$5,989			$4,639
Commercial Airplanes	1,542			1,375
Global Services(1)	1,472			1,257
Defense, Space & Security(1)	760			533
Reinsurance receivables	467			526
Other	348			567
Less valuation allowance	(62		)	(65		)
Total		$10,516			$8,832

⁽¹⁾  Excludes U.S. government contracts

The following table summarizes our accounts receivable under long-term contracts that were unbillable or related to outstanding claims as of December 31:

	Unbillable				Claims
	2017		2016		2017		2016
Current		$2,876		$1,919		$4		$38
Expected to be collected after one year	1,564		2,011			$55	91
Total		$4,440		$3,930		$59		$129

Under contract accounting unbillable receivables on long-term contracts arise when the sales or revenues based on performance attainment, though appropriately recognized, cannot be billed yet under terms of the contract as of the balance sheet date. Any adjustment for the credit quality of unbillable receivables, if required, would be recorded as a direct reduction of revenue. Factors considered in assessing the collectability of unbillable receivables include, but are not limited to, a customer’s extended delinquency, requests for restructuring and filings for bankruptcy. Unbillable receivables related to commercial customers expected to be collected after one year were$172 and $172 at December 31, 2017 and 2016. Accounts receivable related to claims are items that we believe are earned, but are subject to uncertainty concerning their determination or ultimate realization.

Accounts receivable, other than those described above, expected to be collected after one year are not material.