Acquisitions - Narrative (Details) $ in Thousands					9 Months Ended		12 Months Ended
	May 03, 2022 USD ($)	Apr. 01, 2022 company	Mar. 31, 2021 USD ($)	Jan. 31, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Business Acquisition
Number of businesses acquired | company		2
Goodwill					$ 698,682		$ 657,131	$ 560,332
Unrealized (gains) on investments					0	$ 27,825
Open Realty
Business Acquisition
Cash and stock issued at closing	$ 65,534
Contingent consideration	7,322
Goodwill	50,756
Business acquisition, amount deductible for tax	$ 39,400
Business acquisition, aggregate revenue contribution					8,300
Knotel, Inc.
Business Acquisition
Shares issued as compensation							110,400
Cash and stock issued at closing			$ 44,492
Contingent consideration			6,574				6,600
Goodwill			97,639				97,600
Business acquisition, amount deductible for tax							78,300
Business acquisition, aggregate revenue contribution							75,600
Debtor-in-possession facility financing costs				$ 19,800
First and second lien debt			39,584				39,600
Debtor-in-possession financing			$ 19,788				19,800
Cash and stock issued at closing							41,500
Stock issued at closing							3,000
Deskeo
Business Acquisition
Debt securities							13,800
Unrealized (gains) on investments							$ 27,800
Restricted Stock Units | Open Realty
Business Acquisition
Shares issued as compensation					$ 72,900