REVENUE

We classify revenue in three categories: service revenue, revenue from reimbursable expenses and non-controlling interests. Service revenue consists of amounts attributable to our fee-based services and sales of short-term investments in real estate. Reimbursable expenses and non-controlling interests are pass-through items for which we earn no margin. Reimbursable expenses consist of amounts we incur on behalf of our customers in performing our fee-based services that we pass directly on to our customers without a markup. Non-controlling interests represent the earnings of Lenders One, a consolidated entity that is a mortgage cooperative managed, but not owned, by Altisource. Lenders One is included in revenue and reduced from net income to arrive at net income attributable to Altisource (see Note 2). The components of revenue were as follows for the years ended December 31:



(in thousands)	2018		2017		2016

Service revenue	$	805,480	$	899,561	$	942,599
Reimbursable expenses	30,039		39,912		52,011
Non-controlling interests	2,683		2,740		2,693

Total	$	838,202	$	942,213	$	997,303

As discussed in Note 2, the Company adopted Topic 606 effective January 1, 2018 using the cumulative effect method.

Disaggregation of Revenue

Disaggregation of total revenues by segments and major source is as follows:



	Twelve months ended December 31, 2018
(in thousands)	Revenue recognized when services are performed or assets are sold		Revenue related to technology platforms and professional services		Reimbursable expenses revenue		Total revenue

Mortgage Market:
Servicer Solutions	$	537,161	$	73,782	$	28,207	$	639,150
Origination Solutions	38,597		8,909		249		47,755
Total Mortgage Market	575,758		82,691		28,456		686,905

Real Estate Market:
Consumer Real Estate Solutions	8,593		—		2		8,595
Real Estate Investor Solutions	80,162		—		1,533		81,695
Total Real Estate Market	88,755		—		1,535		90,290

Other Businesses, Corporate and Eliminations	55,226		5,733		48		61,007

Total revenue	$	719,739	$	88,424	$	30,039	$	838,202

Contract Balances

Our contract assets consist of unbilled accounts receivable (see Note 7). Our contract liabilities consist of current deferred revenue as reported on the consolidated balance sheets and non-current deferred revenue (see Note 15). Revenue recognized that was included in the contract liability at the beginning of the period, including amounts added to the contract liability as part of the cumulative effect of adopting Topic 606, was $20.6 million for the year ended December 31, 2018.