Deferred Revenue (Tables)

9 Months Ended

Sep. 30, 2020

Revenue from Contract with Customer [Abstract]

Schedule of Changes in Deferred Revenue

The changes in our deferred revenue during the nine months ended September 30, 2020 are as follows (in millions):

	Annual Listings Revenues		Original Listings Revenues		Other Listings Revenues		Data Services and Other Revenues		Mortgage Technology		Total
Deferred revenue balance at December 31, 2019	$	—	$	19	$	94	$	88	$	—	$	201
Additions	384		9		34		367		25		819
Amortization	(288)		(15)		(31)		(326)		—		(660)
Deferred revenue balance at September 30, 2020	$	96	$	13	$	97	$	129	$	25	$	360

The changes in our deferred revenue during the nine months ended September 30, 2019 are as follows (in millions):

	Annual Listings Revenues		Original Listings Revenues		Other Listings Revenues		Data Services and Other Revenues		Total
Deferred revenue balance at December 31, 2018	$	—	$	25	$	100	$	92	$	217
Additions	387		11		30		300		728
Amortization	(289)		(17)		(30)		(277)		(613)
Deferred revenue balance at September 30, 2019	$	98	$	19	$	100	$	115	$	332