Revenue

Disaggregation of Revenues

The following table presents net sales disaggregated by product line for each segment:



	Three Months Ended
	March 31,
(in millions)	2019		2018
Fluid Handling
Process Valves and Related Products	$	168.0	$	165.0
Commercial Valves	80.8		80.5
Other Products	24.9		21.1
Total Fluid Handling	$	273.7	$	266.6

Payment & Merchandising Technologies
Payment Acceptance and Dispensing Products	$	158.8	$	145.4
Banknotes and Security Products	98.6		99.8
Merchandising Equipment	46.4		47.2
Total Payment & Merchandising Technologies	$	303.8	$	292.4

Aerospace & Electronics
Commercial Original Equipment	$	90.3	$	84.7
Military and Other Original Equipment	51.5		42.1
Commercial Aftermarket Products	38.2		32.6
Military Aftermarket Products	14.6		11.0
Total Aerospace & Electronics	$	194.6	$	170.4

Engineered Materials
FRP - Recreational Vehicles	$	26.6	$	37.4
FRP - Building Products	23.6		23.8
FRP - Transportation	9.4		8.5
Total Engineered Materials	$	59.6	$	69.7

Total net sales	$	831.7	$	799.1

Remaining Performance Obligations

The transaction price allocated to remaining performance obligations represents the transaction price of firm orders which have not yet been fulfilled, which we also refer to as total backlog. As of March 31, 2019, backlog was $1,106.5 million. We expect to recognize approximately 87% of our remaining performance obligations as revenue in 2019, an additional 10% by 2020 and the balance thereafter.

Contract Assets and Contract Liabilities

Contract assets represent unbilled amounts that typically arise from contracts for customized products or contracts for products sold directly to the U.S. government or indirectly to the U.S. government through subcontracts, where revenue recognized using the cost-to-cost method exceeds the amount billed to the customer. Contract assets are assessed for impairment and recorded at their net realizable value. Contract liabilities represent advance payments from customers. Revenue related to contract liabilities is recognized when control is transferred to the customer. We report contract assets, which are included within “Other current assets” in our Condensed Consolidated Balance Sheets, and contract liabilities, which are included within “Accrued liabilities” on our Condensed Consolidated Balance Sheets, on a contract-by-contract net basis at the end of each reporting period. Net contract assets and contract liabilities consisted of the following:



(in millions)	March 31, 2019		December 31, 2018
Contract assets	$	58.9	$	54.9
Contract liabilities	$	40.8	$	50.8

Revenue recognized in the three-month periods ended March 31, 2019 and 2018, that was included in the contract liability balance at the beginning of each year was $16.7 million and $10.8 million, respectively.