Investment in Loans Schedule of Geographic concentration - Reverse Mortgage Loans (Details) - Financing Receivables, Unpaid Principal Balance [Member] - Geographic Concentration Risk [Member] - Reverse mortgage loans	3 Months Ended	9 Months Ended
	Mar. 31, 2025	Sep. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	100.00%	100.00%
CALIFORNIA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	29.40%	29.80%
FLORIDA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	8.80%	8.90%
COLORADO
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	7.10%	6.70%
ARIZONA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	6.40%	6.30%
WASHINGTON
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	5.40%	5.20%
UTAH
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	5.10%	4.90%
TEXAS
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	5.10%	5.00%
OREGON
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	3.00%	2.80%
MASSACHUSETTS
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	2.10%	2.20%
IDAHO
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	2.70%	2.60%
NEW YORK
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	2.30%	2.60%
NEVADA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	2.10%	2.10%
NORTH CAROLINA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	2.20%	2.20%
VIRGINIA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.40%	1.40%
OHIO
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.40%	1.40%
MARYLAND
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	0.90%	0.90%
NEW JERSEY
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.20%	1.30%
SOUTH CAROLINA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.40%	1.40%
GEORGIA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.70%	1.70%
NEW JERSEY
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.00%	1.00%
TENNESSEE
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	1.40%	1.50%
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Outstanding Unpaid Principal Balance	7.90%	8.10%