Financial Guarantee Liability - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) loan	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) loan	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) loan
Guarantor Obligations
Outstanding loan balances	$ 26,700,000		$ 26,700,000		$ 25,800,000
Maximum loss potential	8,100,000		8,100,000		7,800,000
Provision for expected credit losses	300	$ 4,700	89	$ 6,300	3,592
Delinquent
Guarantor Obligations
Outstanding loan balances	22,800		22,800		33,600
Maximum loss potential	$ 7,600		$ 7,600		$ 11,200
Number of loans | loan	1		1		2
Liquidation value of loans outstanding	$ 20,000		$ 20,000		$ 28,400
Potential loss on liquidation of loan			$ 700	$ 2,300
Foreclosure
Guarantor Obligations
Number of loans | loan	1		1
Fannie Mae DUS or Freddie TAH Loans | Maximum
Guarantor Obligations
Percentage of contingent liability of actual losses incurred on outstanding loans			33.00%