The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Intangible Assets, net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Indefinite-lived Intangible Assets [Line Items]
Amortization of website development costs and intangible assets included in technology and development	$ 13,100		$ 11,000	$ 24,900	$ 22,000
Non-cash impairment charge				76,800	$ 0
Trade names and trademarks \| Trulia
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible asset		$ 108,000
Non-cash impairment charge		71,500
Fair value of the intangible asset	$ 36,500	$ 36,500		$ 36,500
Useful life				10 years