Contracts with Customers Contracts with Customers

12 Months Ended

Dec. 31, 2018

Contracts with Customers [Abstract]

Long-term Contracts or Programs Disclosure

Contracts with Customers

Unbilled receivables increased from $8,194 at December 31, 2017 to $10,025 at December 31, 2018, primarily driven by revenue recognized at BDS, BGS and BCA in excess of billings.

Advances and progress billings increased from $48,042 at December 31, 2017 to $50,676 at December 31, 2018, primarily driven by advances on orders received in excess of revenue recognized at BCA.

Revenues recognized for the years ended December 31, 2018 and 2017 from amounts recorded as Advances and progress billings at the beginning of each year were $24,737 and $22,796.

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

	Unbilled				Claims
	2018		2017		2018		2017
Current		$7,178		$5,149		$1		$4
Expected to be collected after one year	2,847		3,045		2		55
Total		$10,025		$8,194		$3		$59

Unbilled receivables related to commercial customers expected to be collected after one year were $150 and $172 at December 31, 2018 and 2017. Unbilled receivables related to claims are items that we believe are earned, but are subject to uncertainty concerning their determination or ultimate realization.