2. REVENUE FROM CONTRACTS WITH CUSTOMERS

The following table summarizes revenue from contracts with customers:



	Three Months Ended March 31,
thousands	2019			2018
Revenue from customers
Service revenues – fee based	$	579,974		$	393,773
Service revenues – product based	19,379			23,423
Product sales	72,800			84,868
Total revenue from customers	672,153			502,064
Revenue from other than customers
Net gains (losses) on commodity price swap agreements	(667		)	(1,243		)
Other	397			233
Total revenues and other	$	671,883		$	501,054

Contract balances. Receivables from customers, which are included in Accounts receivable, net on the consolidated balance sheets were $315.3 million and $214.3 million as of March 31, 2019, and December 31, 2018, respectively.

Contract assets primarily relate to accrued deficiency fees the Partnership 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, 2018	$	47,621
Amounts transferred to Accounts receivable, net that were included in the contract assets balance at the beginning of the period	(1,376		)
Additional estimated revenues recognized	3,810
Balance at March 31, 2019	$	50,055

Contract assets at March 31, 2019
Other current assets	$	7,172
Other assets	42,883
Total contract assets from contracts with customers	$	50,055

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, 2018	$	145,624
Cash received or receivable, excluding revenues recognized during the period	15,213
Revenues recognized that were included in the contract liability balance at the beginning of the period	(9,279		)
Balance at March 31, 2019	$	151,558

Contract liabilities at March 31, 2019
Accrued liabilities	$	6,364
Other liabilities	145,194
Total contract liabilities from contracts with customers	$	151,558

Transaction price allocated to remaining performance obligations. Revenues expected to be recognized from certain performance obligations that are unsatisfied (or partially unsatisfied) as of March 31, 2019, are reflected in the following table. The Partnership 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
Remainder of 2019	$	532,477
2020	862,428
2021	911,450
2022	976,136
2023	932,921
Thereafter	4,500,175
Total	$	8,715,587