Debt Obligations, Net - Schedule of Debt Obligations (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) facility	Dec. 31, 2023 USD ($) facility	Jun. 30, 2024 USD ($)	Jan. 31, 2024 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 3,821,112	$ 3,249,158
Carrying Value of Collateral	4,129,209	3,405,564
Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 3,801,446	$ 3,239,123
Short-Term Warehouse Facilities and Other: | Residential consumer loan warehouse facilities | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	7	4
Debt Instrument, Face Amount	$ 1,269,512	$ 796,537
Facility Capacity	$ 2,675,000	$ 1,150,000
Weighted Average Interest Rate (as percent)	6.69%	7.27%
Carrying Value of Collateral	$ 1,350,551	$ 907,742
Short-Term Warehouse Facilities and Other: | Residential consumer loan warehouse facilities | Facilities | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 1,269,512	$ 796,537
Short-Term Warehouse Facilities and Other: | Residential investor loan warehouse facilities | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	3	2
Debt Instrument, Face Amount	$ 277,536	$ 71,851
Facility Capacity	$ 900,000	$ 455,000
Weighted Average Interest Rate (as percent)	8.29%	8.14%
Carrying Value of Collateral	$ 422,636	$ 95,225
Short-Term Warehouse Facilities and Other: | Residential investor loan warehouse facilities | Facilities | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 276,827	$ 71,719
Short-Term Warehouse Facilities and Other: | Real estate securities repurchase facilities | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	6	3
Debt Instrument, Face Amount	$ 185,393	$ 82,622
Facility Capacity	$ 0	$ 0
Weighted Average Interest Rate (as percent)	6.45%	7.01%
Carrying Value of Collateral	$ 250,416	$ 122,110
Short-Term Warehouse Facilities and Other: | Real estate securities repurchase facilities | Facilities | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 185,393	$ 82,622
Short-Term Warehouse Facilities and Other: | Residential MSR warehouse facility | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1	1
Debt Instrument, Face Amount	$ 54,306	$ 47,858
Facility Capacity	$ 75,000	$ 50,000
Weighted Average Interest Rate (as percent)	8.25%	8.60%
Carrying Value of Collateral	$ 80,392	$ 76,560
Short-Term Warehouse Facilities and Other: | Residential MSR warehouse facility | Facilities | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 54,306	$ 47,858
Short-Term Warehouse Facilities and Other: | HEI warehouse facility | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1	1
Debt Instrument, Face Amount	$ 100,302	$ 122,659
Facility Capacity	$ 150,000	$ 150,000
Weighted Average Interest Rate (as percent)	9.52%	9.89%
Carrying Value of Collateral	$ 210,288	$ 237,973
Short-Term Warehouse Facilities and Other: | HEI warehouse facility | Facilities | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 100,302	$ 122,659
Short-Term Warehouse Facilities and Other: | Servicer advance financing | Servicer advance financing
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1	1
Debt Instrument, Face Amount	$ 156,116	$ 154,369
Facility Capacity	$ 240,000	$ 240,000
Weighted Average Interest Rate (as percent)	7.31%	7.71%
Carrying Value of Collateral	$ 212,446	$ 225,345
Short-Term Warehouse Facilities and Other: | Servicer advance financing | Servicer advance financing | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 155,986	$ 153,654
Recourse Subordinate Securities Financing: | Sequoia securities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility		1
Debt Instrument, Face Amount		$ 124,552
Weighted Average Interest Rate (as percent)		7.21%
Carrying Value of Collateral		$ 175,096
Recourse Subordinate Securities Financing: | Sequoia securities | Carrying Value
Debt Instrument [Line Items]
Carrying Value		$ 124,552
Recourse Subordinate Securities Financing: | CAFL securities 1
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility		1
Debt Instrument, Face Amount		$ 101,228
Weighted Average Interest Rate (as percent)		5.71%
Carrying Value of Collateral		$ 124,793
Recourse Subordinate Securities Financing: | CAFL securities 1 | Carrying Value
Debt Instrument [Line Items]
Carrying Value		$ 101,228
Recourse Subordinate Securities Financing: | CAFL securities 2
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1	1
Debt Instrument, Face Amount	$ 269,037	$ 57,982
Weighted Average Interest Rate (as percent)	7.54%	4.75%
Carrying Value of Collateral	$ 324,874	$ 112,813
Recourse Subordinate Securities Financing: | CAFL securities 2 | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 267,833	$ 57,982
Long-Term Warehouse Facilities: | Residential Investor Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	4	6
Debt Instrument, Face Amount	$ 696,671	$ 1,023,384
Facility Capacity	$ 1,625,000	$ 2,350,000
Weighted Average Interest Rate (as percent)	8.16%	8.14%
Carrying Value of Collateral	$ 987,286	$ 1,327,907
Long-Term Warehouse Facilities: | Residential Investor Facilities | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 695,431	$ 1,021,708
Corporate Debt: | Promissory notes | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	3	3
Debt Instrument, Face Amount	$ 13,663	$ 16,063
Facility Capacity	$ 0
Weighted Average Interest Rate (as percent)	7.02%	6.97%
Carrying Value of Collateral	$ 0	$ 0
Corporate Debt: | Promissory notes | Carrying Value | Facilities
Debt Instrument [Line Items]
Carrying Value	$ 13,663	$ 16,063
Corporate Debt: | Corporate Secured Revolving Financing Facility | Facilities
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1
Debt Instrument, Face Amount	$ 150,000
Facility Capacity	$ 250,000
Weighted Average Interest Rate (as percent)	10.02%
Carrying Value of Collateral	$ 290,320
Corporate Debt: | Corporate Secured Revolving Financing Facility | Carrying Value | Facilities
Debt Instrument [Line Items]
Carrying Value	$ 144,281
Corporate Debt: | 5.625% convertible senior notes | Convertible Debt
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility		1
Debt Instrument, Face Amount		$ 142,977
Weighted Average Interest Rate (as percent)		5.625%
Corporate Debt: | 5.625% convertible senior notes | Carrying Value | Convertible Debt
Debt Instrument [Line Items]
Carrying Value		$ 142,558
Corporate Debt: | 5.75% exchangeable senior notes | Exchangeable Senior Notes
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1	1
Debt Instrument, Face Amount	$ 156,666	$ 156,666
Weighted Average Interest Rate (as percent)	5.75%	5.75%
Corporate Debt: | 5.75% exchangeable senior notes | Carrying Value | Exchangeable Senior Notes
Debt Instrument [Line Items]
Carrying Value	$ 155,772	$ 155,138
Corporate Debt: | 7.75% convertible senior notes | Convertible Debt
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1	1
Debt Instrument, Face Amount	$ 207,410	$ 210,910
Weighted Average Interest Rate (as percent)	7.75%	7.75%
Corporate Debt: | 7.75% convertible senior notes | Carrying Value | Convertible Debt
Debt Instrument [Line Items]
Carrying Value	$ 203,525	$ 206,032
Corporate Debt: | Trust preferred securities and subordinated notes
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	2	2
Debt Instrument, Face Amount	$ 139,500	$ 139,500
Weighted Average Interest Rate (as percent)	7.77%	7.90%
Corporate Debt: | Trust preferred securities and subordinated notes | Carrying Value
Debt Instrument [Line Items]
Carrying Value	$ 138,848	$ 138,813
Corporate Debt: | 9.125% Senior Notes | Unsecured Debt
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1
Debt Instrument, Face Amount	$ 60,000			$ 60,000
Weighted Average Interest Rate (as percent)	9.125%
Corporate Debt: | 9.125% Senior Notes | Carrying Value | Unsecured Debt
Debt Instrument [Line Items]
Carrying Value	$ 57,776
Corporate Debt: | 9.0% Senior Notes | Unsecured Debt
Debt Instrument [Line Items]
Number of Facilities or Issuances | facility	1
Debt Instrument, Face Amount	$ 85,000		$ 85,000
Weighted Average Interest Rate (as percent)	9.00%		9.00%
Corporate Debt: | 9.0% Senior Notes | Carrying Value | Unsecured Debt
Debt Instrument [Line Items]
Carrying Value	$ 81,991