Description of Business and Summary of Significant Accounting Policies - Merger (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Jul. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Jul. 29, 2020 shares	Jan. 01, 2019 USD ($)
Common Stock and Redeemable Convertible Preferred Stock
Trust fund		$ 196,046	$ 4,179
Common stock, shares outstanding | shares	21,562,100	81,669,151	34,197,822
Common stock, shares issued | shares		81,669,151	34,197,822	21,562,100
Earn out shares issued | shares	150,000
Earnout liability Assumed		$ 50,442
Merger transaction cost	$ 5,600
Contributed capital	269,500
Payment of capital distribution	$ 50,400
Impairment loss		0	$ 0
Cash balance at bank		206,000
Percentage of shares held by pre closing holders	55.00%
Retained Earnings (Accumulated Deficit)		(315,083)	$ (263,474)
Cumulative effect | ASC 606
Common Stock and Redeemable Convertible Preferred Stock
Retained Earnings (Accumulated Deficit)					$ 507
Additional Offering, PIPE Investors
Common Stock and Redeemable Convertible Preferred Stock
Common stock, shares issued | shares	15,000,000
Shares issued Price (Per share) | $ / shares	$ 10.00
Net proceeds	$ 141,800
Direct offering costs	8,200
PropTech Acquisition Corporation
Common Stock and Redeemable Convertible Preferred Stock
Working capital	600
Payment of Liabilities	4,300
Proceeds available for use	305,100
Payment of capital distribution	30,000
Net assets		$ 275,100
PropTech Acquisition Corporation | Original public offering
Common Stock and Redeemable Convertible Preferred Stock
Working capital	$ 6,000
Merger Agreement
Common Stock and Redeemable Convertible Preferred Stock
Shares Redeemed | shares	400
Redemption price (per share) | $ / shares	$ 10.04
Trust fund	$ 173,100
Common stock, shares outstanding | shares	17,249,600
Shares converted | shares	4,312,500
Shares conversion ratio	1
Shares issued on conversion | shares	184,652
Warrants cancelled | shares	3,116,003
Issued for cancellation of warrants | shares	5,126,128
Common stock issued on extinguishment of stock options | shares	2,533,016
Shares issued value in merger	$ 30,000
Shares issued shares in merger | shares	83,559,663
Earn out shares issued | shares	6,000,000
Merger Agreement | Common stock warrants
Common Stock and Redeemable Convertible Preferred Stock
Issued for cancellation of warrants | shares	4,472,695
Merger Agreement | Preferred stock
Common Stock and Redeemable Convertible Preferred Stock
Shares converted | shares	52,251,876
Shares issued on conversion | shares	52,207,029
Common stock issued on extinguishment of stock options | shares	2,316,280
Merger Agreement | PropTech Acquisition Corporation
Common Stock and Redeemable Convertible Preferred Stock
Shares issued (shares) | shares	36,264,984