Loans - Secured Loans Distributed within California (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal		$ 54,589	$ 57,292	$ 60,088
Loans - percent		100.00%		100.00%
San Francisco [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal	[1]	$ 17,645		$ 18,425
Loans - percent	[1]	32.30%		30.70%
San Mateo [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal				$ 2,519	[1]
Loans - percent	[1]	0.00%		4.20%
Santa Clara [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal	[1]	$ 12,214		$ 12,266
Loans - percent	[1]	22.40%		20.40%
Solano [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal	[1]	$ 3,550		$ 3,550
Loans - percent	[1]	6.50%		5.90%
Marin [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal	[1]	$ 1,500		$ 1,099
Loans - percent	[1]	2.70%		1.80%
Alameda [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal	[1]	$ 1,246		$ 1,687
Loans - percent	[1]	2.30%		2.80%
San Francisco Bay Area [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal	[1]	$ 36,155		$ 39,546
Loans - percent	[1]	66.20%		65.80%
Stanislaus [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal		$ 634		$ 1,301
Loans - percent		1.20%		2.20%
Northern California [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal		$ 36,789		$ 40,847
Loans - percent		67.40%		68.00%
Los Angeles [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal		$ 4,600		$ 5,597
Loans - percent		8.40%		9.30%
Orange [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal		$ 13,200		$ 11,600
Loans - percent		24.20%		19.30%
Santa Barbara [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal				$ 2,044
Loans - percent		0.00%		3.40%
Southern California [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Secured loans, principal		$ 17,800		$ 19,241
Loans - percent		32.60%		32.00%

[1] Includes the Silicon Valley