Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Revenue	$ 1,113.9	$ 619.9
Operating expenses
Commissions and other related expense	942.2	508.8
Sales and marketing	111.3	106.5
Operations and support	70.0	61.1
Research and development	96.6	38.8
General and administrative	92.9	26.5
Depreciation and amortization	13.5	12.4
Total operating expenses	1,326.5	754.1
Loss from operations	(212.6)	(134.2)
Investment income, net	0.0	1.5
Interest expense	(0.5)
Loss before income taxes	(213.1)	(132.7)
Benefit from income taxes	0.7	0.0
Net loss	$ (212.4)	$ (132.7)
Net loss per share attributable to common stockholders, basic and diluted	$ (1.67)	$ (1.22)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted	126,917,284	108,764,426

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585