Revenue

Disaggregation of Revenue

The following table represents a disaggregation of revenue by timing of revenue along with the reportable segment for each category:



	Three Months Ended March 31, 2019
	Energy & Chemicals		D&S West		D&S East		Intersegment Eliminations			Consolidated
Point in time	$	74.1	$	107.4	$	63.9	$	(3.0	)	$	242.4
Over time	31.5		10.6		4.8		—			46.9
Total	$	105.6	$	118.0	$	68.7	$	(3.0	)	$	289.3



	Three Months Ended March 31, 2018
	Energy & Chemicals		D&S West		D&S East		Intersegment Eliminations			Consolidated
Point in time	$	23.9	$	91.3	$	50.5	$	(1.5	)	$	164.2
Over time	66.0		9.3		4.6		—			79.9
Total	$	89.9	$	100.6	$	55.1	$	(1.5	)	$	244.1

Refer to Note 3, “Reportable Segments,” for a table of revenue disaggregated by product application along with the reportable segment for each category.

Contract Balances

The following table represents changes in our contract assets and contract liabilities balances:



	March 31, 2019		December 31, 2018		Year-to-date Change ($)			Year-to-date Change (%)
Contract assets
Accounts receivable, net of allowances	$	205.2	$	194.8	10.4			5.3	%
Unbilled contract revenue	68.9		54.5		14.4			26.4	%

Contract liabilities
Customer advances and billings in excess of contract revenue	$	129.5	$	130.0	$	(0.5	)	(0.4	)%
Long-term deferred revenue	1.3		1.4		(0.1		)	(7.1	)%

Revenue recognized for the three months ended March 31, 2019 and 2018, that was included in the contract liabilities balance at the beginning of each year was $37.0, and $38.9, respectively. The amount of revenue recognized during the three months ended March 31, 2019 from performance obligations satisfied or partially satisfied in previous periods as a result of changes in the estimates of variable consideration related to long-term contracts, was not significant.

Remaining Performance Obligations

Remaining performance obligations represent the transaction price of firm signed purchase orders or other written contractual commitments from customers for which work has not been performed, or is partially completed, and excludes unexercised contract options and potential orders. As of March 31, 2019, the estimated revenue expected to be recognized in the future related to remaining performance obligations was $733.8. We expect to recognize revenue on approximately 68.5% of the remaining performance obligations over the next 12 months and with the remaining over the next few years thereafter.