Subsequent Event	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Event	SUBSEQUENT EVENTThe Company’s Proposed Spin-offOn November 8, 2021, the Company announced its intention to spin off its real estate services and PropTech investment business (the "Proposed Spin-off") through a pro rata distribution of all of the outstanding shares of common stock of its newly formed wholly-owned subsidiary Douglas Elliman Inc. (“Spinco”) to holders of the Company’s common stock (including common stock underlying outstanding stock option awards and restricted stock awards). The Proposed Spin-off is intended to be a tax-free transaction for U.S. federal income tax purposes and is expected to be completed by the end of calendar year 2021, subject to the satisfaction of customary conditions, including final approval by the Company’s board of directors and the effectiveness of Spinco’s registration statement on Form 10 to be filed with the SEC.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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