Secured Borrowings - Secured Financing Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Secured Borrowings
Secured financing agreements, net	$ 12,678,948	$ 11,151,557
Borrowing Base Facility
Secured Borrowings
Maximum Facility Size	615,000
Maximum facility size subject to certain conditions	1,300,000
Commercial Financing Facilities
Secured Borrowings
Maximum Facility Size	878,100
Secured Borrowings
Secured Borrowings
Maximum Facility Size	24,641,651
Long term debt, gross	12,780,793	11,236,129
Unamortized net discount	(19,084)	(19,338)
Unamortized deferred financing costs	(82,761)	(65,234)
Secured financing agreements, net	12,678,948	11,151,557
Secured Borrowings \| Borrowing Base Facility
Secured Borrowings
Maximum Facility Size	1,250,000
Long term debt, gross	2,000	2,000
Secured Borrowings \| Commercial Financing Facilities
Secured Borrowings
Maximum Facility Size	978,143
Long term debt, gross	480,611	330,081
Secured Borrowings \| Infrastructure Financing Facilities
Secured Borrowings
Maximum Facility Size	1,175,000
Long term debt, gross	515,004	499,242
Secured Borrowings \| Property Financing
Secured Borrowings
Maximum Facility Size	1,110,191
Long term debt, gross	622,906	615,854
Secured Borrowings \| Property Financing \| Fundamental Income Properties, LLC
Secured Borrowings
Long term debt, gross	115,300
Secured Borrowings \| Term Loans and Revolver
Secured Borrowings
Maximum Facility Size	2,470,180
Long term debt, gross	2,270,180	1,452,567
Equity interests in certain subsidiaries used to secure facilities	7,700,000
Secured Borrowings \| Total Other Secured Financing
Secured Borrowings
Maximum Facility Size	6,983,514
Long term debt, gross	3,890,701	2,899,744
Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	16,039,006
Secured Borrowings \| Asset Pledged as Collateral \| Borrowing Base Facility
Secured Borrowings
Pledged Asset Carrying Value	52,855
Secured Borrowings \| Asset Pledged as Collateral \| Commercial Financing Facilities
Secured Borrowings
Pledged Asset Carrying Value	705,143
Secured Borrowings \| Asset Pledged as Collateral \| Infrastructure Financing Facilities
Secured Borrowings
Pledged Asset Carrying Value	671,973
Secured Borrowings \| Asset Pledged as Collateral \| Property Financing
Secured Borrowings
Pledged Asset Carrying Value	792,501
Amount of debt matured	$ 17,600
Joint venture ownership percentage	75.00%
Secured Borrowings \| Asset Pledged as Collateral \| Total Other Secured Financing
Secured Borrowings
Pledged Asset Carrying Value	$ 2,222,472
Secured Borrowings \| Index \| Commercial Financing Facilities
Secured Borrowings
Basis spread	1.98%
Secured Borrowings \| SOFR \| Borrowing Base Facility
Secured Borrowings
Basis spread	2.00%
Secured Borrowings \| SOFR \| Infrastructure Financing Facilities
Secured Borrowings
Basis spread	1.96%
Secured Borrowings \| SOFR \| Property Financing
Secured Borrowings
Basis spread	2.52%
Secured Borrowings \| SOFR \| Term Loans and Revolver
Secured Borrowings
Basis spread	2.00%
Line of Credit \| Commercial Financing Facilities
Secured Borrowings
Line of credit capacity if conditions are met	$ 978,100
Commercial Loans
Secured Borrowings
Maximum Facility Size	11,800,000
Secured financing agreements, net	2,700,000
Line of credit capacity if conditions are met	12,200,000
Commercial Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	12,243,159
Long term debt, gross	6,048,734	5,137,103
Commercial Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 9,986,198
Commercial Loans \| Secured Borrowings \| Index
Secured Borrowings
Basis spread	1.83%
Residential Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 3,450,000
Long term debt, gross	1,929,400	2,126,692
Residential Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 2,275,806
Residential Loans \| Secured Borrowings \| SOFR
Secured Borrowings
Basis spread	1.65%
Infrastructure Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 650,000
Long term debt, gross	211,651	264,432
Infrastructure Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 299,123
Infrastructure Loans \| Secured Borrowings \| Index
Secured Borrowings
Basis spread	2.00%
Conduit Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 375,000
Long term debt, gross	0	87,061
Conduit Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 0
Conduit Loans \| Secured Borrowings \| SOFR
Secured Borrowings
Basis spread	2.15%
CMBS/RMBS
Secured Borrowings
Secured financing agreements, net	$ 340,500
Coupon Rate	4.02%
Amount outstanding on a repurchase facility not subject to margin calls	$ 319,500
Amount outstanding on repurchase facility	$ 25,800
Pro rata share owned by a non-controlling partner in a consolidated joint venture	49.00%
CMBS/RMBS \| Certain Facilities
Secured Borrowings
Secured financing agreements, net	$ 246,400
CMBS/RMBS \| Certain Facilities \| Maximum
Secured Borrowings
Rolling maturity period	12 months
CMBS/RMBS \| Certain Facilities \| Minimum
Secured Borrowings
Rolling maturity period	6 months
CMBS/RMBS \| SOFR \| Weighted-average
Secured Borrowings
Coupon Rate	1.65%
CMBS/RMBS \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 939,978
Long term debt, gross	700,307	721,097
CMBS/RMBS \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	1,255,407
Total Repurchase Agreements \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	17,658,137
Long term debt, gross	8,890,092	$ 8,336,385
Total Repurchase Agreements \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 13,816,534

The amount outstanding on a repurchase facility

No definition available.

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- Definition

The amount outstanding on a repurchase facility that is not subject to margin calls.

+ References

No definition available.

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- Definition

Debt Instrument, Amount Matured

+ References

No definition available.

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- Definition

Rolling period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Amount of equity interests in certain of the entity's subsidiaries used to secure debt facilities.

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No definition available.

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- Definition

Joint Venture Ownership, Parent

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No definition available.

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- Definition

Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases, Accordion Feature

+ References

No definition available.

+ Details

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- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer, subject to certain conditions defined in the facility agreement.

+ References

No definition available.

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- Definition

Pro rata share owned by a non-controlling partner in a consolidated joint venture.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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