Deferred Revenue (Tables)

3 Months Ended

Mar. 31, 2020

Revenue from Contract with Customer [Abstract]

Schedule of Changes in Deferred Revenue

The changes in our deferred revenue during the three months ended March 31,

2020 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, 2019	$	—		$	19		$	94		$	88		$	201
Additions	381			4			21			186			592
Amortization	(96		)	(5		)	(11		)	(96		)	(208		)
Deferred revenue balance at March 31, 2020	$	285		$	18		$	104		$	178		$	585

The changes in our deferred revenue during the three months ended March 31, 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	382			3			20			139			544
Amortization	(96		)	(6		)	(9		)	(85		)	(196		)
Deferred revenue balance at March 31, 2019	$	286		$	22		$	111		$	146		$	565