CONTRACT ASSETS AND LIABILITIES

6 Months Ended

Jun. 30, 2019

Revenue from Contract with Customer [Abstract]

Contract assets include unbilled amounts typically resulting from sales under contracts when the percentage-of-completion cost-to-cost method of revenue recognition is utilized and revenue recognized exceeds the amount billed to the customer. Contract liabilities include advance payments and billings in excess of revenue recognized. Contract assets and contract liabilities were as follows (in millions):



	June 30, 2019		December 31, 2018
Contract assets	$	10,388	$	9,472
Contract liabilities	6,766		6,491

Contract assets increased $916 million during the six months ended June 30, 2019, primarily due to the recognition of revenue related to the satisfaction or partial satisfaction of performance obligations during the six months ended June 30, 2019 for which we have not yet billed our customers. There were no significant impairment losses related to our contract assets during the quarters and six months ended June 30, 2019 and June 24, 2018.

Contract liabilities increased $275 million during the six months ended June 30, 2019, primarily due to payments received in advance of our satisfaction or partial satisfaction of these performance obligations. During the quarter and six months ended June 30, 2019, we recognized $1.1 billion and $2.9 billion of our contract liabilities at December 31, 2018 as revenue. During the quarter and six months ended June 24, 2018, we recognized $731 million and $2.6 billion of our contract liabilities at December 31, 2017 as revenue.