3. Contract Assets and Liabilities

Contracts with customers usually stipulate the timing of payment, which is defined by the terms found within the various contracts under which work was performed during the period. Therefore, contract assets and liabilities are created when the timing of costs incurred on work performed does not coincide with the billing terms, which frequently include retention provisions contained in each contract.

The Company’s consolidated balance sheets present contract assets which contain unbilled revenue and contract retainages associated with contract work that has been completed and billed but not paid by customers, pursuant to retainage provisions, that are generally due once the job is completed and approved. The allowance for doubtful accounts associated with contract assets was $0.4 million as of March 31, 2020 and $0.1 million as of December 31, 2019.

Contract assets consisted of the following:


	March 31,		December 31,
(in thousands)	2020		2019		Change

Unbilled revenue, net	$	128,015	$	126,087	$	1,928
Contract retainages, net		95,703		91,022		4,681
Contract assets, net	$	223,718	$	217,109	$	6,609

The Company’s consolidated balance sheets present contract liabilities which contain deferred revenue and an accrual for contracts in a loss provision.

Contract liabilities consisted of the following:


	March 31,		December 31,
(in thousands)	2020		2019		Change

Deferred revenue	$	98,597	$	102,673	$	(4,076)
Accrued loss provision		2,038		2,813		(775)
Contract liabilities	$	100,635	$	105,486	$	(4,851)

The following table provides information about contract assets and contract liabilities from contracts with customers:


	March 31,		December 31,
(in thousands)	2020		2019		Change

Contract assets, net	$	223,718	$	217,109	$	6,609
Contract liabilities		(100,635)		(105,486)		4,851
Net contract assets (liabilities)	$	123,083	$	111,623	$	11,460

The difference between the opening and closing balances of the Company’s contract assets and contract liabilities primarily results from the timing of the Company’s billings in relation to its performance of work. The amounts of revenue recognized in the period that were included in the opening contract liability balances were $25.7 million for the three months ended March 31, 2020 and $21.8 million for the three months ended March 31, 2019. This revenue consists primarily of work performed on previous billings to customers.

The net asset position for contracts in process consisted of the following:


	March 31,		December 31,
(in thousands)	2020		2019

Costs and estimated earnings on uncompleted contracts	$	3,455,512	$	3,532,886
Less: billings to date		3,426,094		3,509,472
	$	29,418	$	23,414

The net asset position for contracts in process is included within the contract asset and contract liability in the accompanying consolidated balance sheets as follows:


	March 31,		December 31,
(in thousands)	2020		2019

Unbilled revenue	$	128,015	$	126,087
Deferred revenue		(98,597)		(102,673)
	$	29,418	$	23,414