Revenue from Contracts with Customers

The following table summarizes revenues from our contracts disaggregated by revenue generating activity contained therein for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
(in thousands)	2019		2018
Dayrate drilling	$	56,451	$	23,777
Mobilization	1,260		459
Reimbursables	1,604		1,231
Capital modification	10		160
Intangible	1,033		—
Total revenue	$	60,358	$	25,627

The following table provides information about receivables, contract assets and contract liabilities related to contracts with customers:



(in thousands)	March 31, 2019			December 31, 2018
Receivables, which are included in “Accounts receivable, net”	$	41,782		$	41,987
Contract assets	$	—		$	—
Contract liabilities	$	(1,121	)	$	(1,374	)

Significant changes in contract assets and contract liabilities balances during the period are as follows:



	Three Months Ended March 31, 2019
(in thousands)	Contract Assets		Contract Liabilities
Revenue recognized that was included in contract liabilities at beginning of period	$	—	$	732
Increase in contract liabilities due to cash received, excluding amounts recognized as revenue	$	—	$	(479	)
Transferred to receivables from contract assets at beginning of period	$	—	$	—

The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) as of March 31, 2019. The estimated revenue does not include amounts of variable consideration that are constrained.



	Year Ending December 31,
(in thousands)	2019		2020		2021		Total
Revenue	$	1,121	$	—	$	—	$	1,121

The amounts presented in the table above consist only of fixed consideration related to fees for rig mobilizations and demobilizations, if applicable, which are allocated to the drilling services performance obligation as such performance obligation is satisfied. We have elected the exemption from disclosure of remaining performance obligations for variable consideration. Therefore, dayrate revenue to be earned on a rate scale associated with drilling conditions and level of service provided for each fractional-hour time increment over the contract term and other variable consideration such as penalties and reimbursable revenues, have been excluded from the disclosure.

Contract Costs

We capitalize costs incurred to fulfill our contracts that (i) relate directly to the contract, (ii) are expected to generate resources that will be used to satisfy our performance obligations under the contract and (iii) are expected to be recovered through revenue generated under the contract. These costs, which principally relate to rig mobilization costs at the commencement of a new contract, are deferred as a current or noncurrent asset (depending on the length of the contract term), and amortized ratably to contract drilling expense as services are rendered over the initial term of the related drilling contract. Such contract costs, recorded as “Prepaid expenses and other current assets”, amounted to $1.0 million and $1.1 million on our consolidated balance sheets at March 31, 2019 and December 31, 2018, respectively. During the quarter ended March 31, 2019, contract costs increased by $0.5 million and we amortized $0.7 million of contract costs.