Property and equipment, net, are stated at cost, subject to review of impairment, and depreciated using the straight-line method over the estimated useful lives of the assets as follows:



Building		39 years
Computer equipment and software		3-5 years
Furniture and fixtures		3-7 years
Leasehold and other improvements		shorter of the lease term or estimated useful life



	December 31,
	2019			2018
Computer equipment	$	680,160		$	493,536
Computer software	59,511			58,303
Leasehold and other improvements	125,299			74,721
Furniture and fixtures	53,651			42,551
Building⁽¹⁾	—			6,551
Construction in progress⁽¹⁾	6,830			10,167
Property and equipment, gross	925,451			685,829
Less: Accumulated depreciation	(457,366		)	(338,613		)
Property and equipment, net	$	468,085		$	347,216

We adopted Topic 842 using the modified retrospective method as of January 1, 2019 and derecognized $10.6 million in building and construction in progress assets that we were previously deemed to own under the prior lease accounting standards. These assets are recognized under our operating lease right-of-use assets under Topic 842 as of December 31, 2019.