2. REVENUE FROM CONTRACTS WITH CUSTOMERS

The following table summarizes revenue from contracts with customers:



thousands	Year Ended December 31, 2018
Revenue from customers
Service revenues – fee based	$	1,609,245
Service revenues – product based	85,553
Product sales	301,867
Total revenue from customers	1,996,665
Revenue from other than customers
Net gains (losses) on commodity price swap agreements	(7,875		)
Other	1,486
Total revenues and other	$	1,990,276

Contract balances. Receivables from customers, which are included in Accounts receivable, net on the consolidated balance sheets were $210.0 million and $244.4 million as of December 31, 2018 and 2017, respectively.

Contract assets primarily relate to accrued deficiency fees WES expects to charge customers once the related performance periods are completed. The following table summarizes the current period activity related to contract assets from contracts with customers:



thousands
Balance at December 31, 2017	$	—
Cumulative effect of adopting Topic 606	5,129
Amounts transferred to Accounts receivable, net from contract assets recognized in the adoption effect	(4,952		)
Additional estimated revenues recognized	5,414
Balance at December 31, 2018	$	5,591

Contract assets at December 31, 2018
Other current assets	$	5,399
Other assets	192
Total contract assets from contracts with customers	$	5,591

2. REVENUE FROM CONTRACTS WITH CUSTOMERS (CONTINUED)

Contract liabilities primarily relate to (i) fees that are charged to customers for only a portion of the contract term and must be recognized as revenues over the expected period of customer benefit, (ii) fixed and variable fees under cost of service contracts that are received from customers for which revenue recognition is deferred and (iii) aid in construction payments received from customers that must be recognized over the expected period of customer benefit. The following table summarizes the current period activity related to contract liabilities from contracts with customers:



thousands
Balance at December 31, 2017	$	—
Cumulative effect of adopting Topic 606	120,717
Cash received or receivable, excluding revenues recognized during the period	53,064
Assets received from customer	12,933
Revenues recognized during the period that were included in the adoption effect ⁽¹⁾	(11,137		)
Cumulative catch up adjustment for change in estimated consideration due to cost of service rate updates	(21,848		)
Balance at December 31, 2018	$	153,729

Contract liabilities at December 31, 2018
Accrued liabilities	$	16,403
Other liabilities	137,326
Total contract liabilities from contracts with customers	$	153,729


⁽¹⁾	Includes $(7.5) million from a performance obligation satisfied in a previous period related to the arbitration against SWEPI LP (see Note 14).

Transaction price allocated to remaining performance obligations. Revenues expected to be recognized from certain performance obligations that are unsatisfied (or partially unsatisfied) as of December 31, 2018, are reflected in the following table. WGP applies the optional exemptions in Topic 606 and does not disclose consideration for remaining performance obligations with an original expected duration of one year or less or for variable consideration related to unsatisfied (or partially unsatisfied) performance obligations. Therefore, the following table represents only a portion of expected future revenues from existing contracts as most future revenues from customers are dependent on future variable customer volumes and, in some cases, variable commodity prices for those volumes.



thousands
2019	$	470,247
2020	554,099
2021	533,861
2022	530,528
2023	488,603
Thereafter	1,802,153
Total	$	4,379,491