REVENUE FROM CONTRACTS WITH CUSTOMERS

Disaggregated Revenue

The Company provides information, analytics and online marketplaces to the commercial real estate industry and related professionals. The revenues by operating segment and type of service consist of the following (in thousands):



	Year Ended December 31,
	2018						2017
	North America		International		Total		North America		International		Total
Information and analytics
CoStar Suite	$	519,661	$	25,534	$	545,195	$	440,534	$	22,651	$	463,185
Information services	58,708		8,916		67,624		64,503		8,115		72,618
Online marketplaces
Multifamily	405,795		—		405,795		279,855		—		279,855
Commercial property and land	173,137		81		173,218		149,572		—		149,572
Total revenues	$	1,157,301	$	34,531	$	1,191,832	$	934,464	$	30,766	$	965,230

Deferred Revenue

Changes in deferred revenue for the period were as follows (in thousands):



Balance at December 31, 2017	$	45,686
Cumulative effect of adoption of ASC 606	(1,716		)
Balance at January 1, 2018	43,970
Revenue recognized in the current period from the amounts in the beginning balance	(43,121		)
New deferrals, net of amounts recognized in the current period	51,000
Effects of foreign currency	(390		)
Balance at December 31, 2018	$	51,459

Contract Assets

The Company had contract assets of $2 million as of December 31, 2018 and January 1, 2018, which are generated when contractual billing schedules differ from revenue recognition timing. Contract assets represent a conditional right to consideration for satisfied performance obligations that becomes a receivable when the conditions are satisfied.

Commissions

The Company recognized $48 million of amortization of deferred commissions included in selling and marketing expense during the year ended months ended December 31, 2018. The Company determined that no deferred commissions were impaired as of December 31, 2018.

Commissions expense activity for the year ended December 31, 2018 was as follows (in thousands):



	Year Ended December 31, 2018
Commissions incurred	$	72,899
Commissions capitalized in the current period	(53,497		)
Amortization of deferred commissions costs	48,313
Total commissions expense	$	67,715

Refer to Note 2 for the Company's policy on accounting for commissions.

Unsatisfied Performance Obligations

Remaining contract consideration for which revenue has not been recognized due to unsatisfied performance obligations was approximately $193 million at December 31, 2018, which the Company expects to recognize over the next three years. This amount does not include contract consideration for contracts with a duration of one year or less.