Secured Borrowings - Secured Financing Agreements (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Secured Borrowings
Pledged Asset Carrying Value	$ 111,069	$ 113,386
Secured financing agreements, net	14,846,988	14,501,532
Revolving credit facility
Secured Borrowings
Maximum borrowing capacity	150,000
Equity interests in certain subsidiaries used to secure facilities	5,400,000
Borrowing Base Facility
Secured Borrowings
Maximum Facility Size	450,000
Maximum facility size subject to certain conditions	750,000
Commercial Financing Facilities
Secured Borrowings
Maximum Facility Size	$ 358,100
Property Mortgages - Fixed rate
Secured Borrowings
Maturity period	4 years 2 months 12 days
Term Loan Facility
Secured Borrowings
Maximum borrowing capacity	$ 778,800
Floor interest rate (as a percent)	0.75%
Term Loan Facility Maturing November 2027
Secured Borrowings
Maximum borrowing capacity	$ 598,500
Floor interest rate (as a percent)	0.50%
SOFR \| Revolving credit facility
Secured Borrowings
Coupon Rate	2.50%
LIBOR + 2.50% \| Term Loan Facility
Secured Borrowings
Pricing margin	2.50%
Maximum borrowing capacity	$ 386,000
LIBOR + 3.25% \| Term Loan Facility
Secured Borrowings
Pricing margin	3.25%
Maximum borrowing capacity	$ 392,800
Secured Overnight Financing Rate Plus 3.25 Percent \| Term Loan Facility Maturing November 2027
Secured Borrowings
Pricing margin	3.25%
Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 23,282,515
Long term debt, gross	14,946,128	14,610,127
Unamortized net discount	(28,897)	(30,320)
Unamortized deferred financing costs	(70,243)	(78,275)
Secured financing agreements, net	14,846,988	14,501,532
Secured Borrowings \| Borrowing Base Facility
Secured Borrowings
Maximum Facility Size	750,000
Long term debt, gross	9,234	0
Secured Borrowings \| Commercial Financing Facilities
Secured Borrowings
Maximum Facility Size	458,074
Long term debt, gross	256,247	311,825
Secured Borrowings \| Residential Financing Facility
Secured Borrowings
Maximum Facility Size	500,000
Long term debt, gross	474,660	244,418
Secured Borrowings \| Infrastructure Financing Facilities
Secured Borrowings
Maximum Facility Size	1,550,000
Long term debt, gross	$ 776,024	765,265
Secured Borrowings \| Property Mortgages - Fixed rate
Secured Borrowings
Coupon Rate	4.46%
Maximum Facility Size	$ 260,891
Long term debt, gross	260,891	261,100
Secured Borrowings \| Property Mortgages - Variable rate
Secured Borrowings
Maximum Facility Size	850,387
Long term debt, gross	847,625	847,633
Secured Borrowings \| Term Loans and Revolver
Secured Borrowings
Maximum Facility Size	1,527,269
Long term debt, gross	1,377,269	1,380,766
Secured Borrowings \| Total Other Secured Financing
Secured Borrowings
Maximum Facility Size	5,896,621
Long term debt, gross	4,001,950	3,811,007
Secured Borrowings \| First Mortgage and Mezzanine
Secured Borrowings
Long term debt, gross	600,000
Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	18,577,438
Secured Borrowings \| Asset Pledged as Collateral \| Borrowing Base Facility
Secured Borrowings
Pledged Asset Carrying Value	12,018
Secured Borrowings \| Asset Pledged as Collateral \| Commercial Financing Facilities
Secured Borrowings
Pledged Asset Carrying Value	354,323
Secured Borrowings \| Asset Pledged as Collateral \| Residential Financing Facility
Secured Borrowings
Pledged Asset Carrying Value	525,297
Secured Borrowings \| Asset Pledged as Collateral \| Infrastructure Financing Facilities
Secured Borrowings
Pledged Asset Carrying Value	1,020,629
Secured Borrowings \| Asset Pledged as Collateral \| Property Mortgages - Fixed rate
Secured Borrowings
Pledged Asset Carrying Value	364,090
Secured Borrowings \| Asset Pledged as Collateral \| Property Mortgages - Variable rate
Secured Borrowings
Pledged Asset Carrying Value	1,001,298
Secured Borrowings \| Asset Pledged as Collateral \| Total Other Secured Financing
Secured Borrowings
Pledged Asset Carrying Value	$ 3,277,655
Secured Borrowings \| Index \| Commercial Financing Facilities
Secured Borrowings
Pricing margin	1.98%
Secured Borrowings \| Index \| Infrastructure Financing Facilities
Secured Borrowings
Pricing margin	2.08%
Secured Borrowings \| SOFR \| Borrowing Base Facility
Secured Borrowings
Pricing margin	2.11%
Secured Borrowings \| SOFR \| Residential Financing Facility
Secured Borrowings
Pricing margin	2.45%
Secured Borrowings \| LIBOR \| First Mortgage and Mezzanine
Secured Borrowings
Coupon Rate	3.34%
Secured Borrowings \| LIBOR \| First Mortgage and Mezzanine \| Weighted-average
Secured Borrowings
Pricing margin	2.07%
Line of Credit \| Commercial Financing Facilities
Secured Borrowings
Line of credit capacity if conditions are met	$ 458,100
Commercial Loans
Secured Borrowings
Maximum Facility Size	12,100,000
Secured financing agreements, net	2,900,000
Line of credit capacity if conditions are met	$ 12,200,000
Commercial Loans \| Index \| Weighted-average
Secured Borrowings
Pricing margin	3.35%
Commercial Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 12,212,382
Long term debt, gross	7,818,505	7,746,867
Commercial Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 11,206,590
Commercial Loans \| Secured Borrowings \| Index
Secured Borrowings
Pricing margin	2.06%
Residential Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 3,064,671
Long term debt, gross	1,967,984	1,912,774
Residential Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 2,204,038
Residential Loans \| Secured Borrowings \| SOFR
Secured Borrowings
Pricing margin	2.22%
Infrastructure Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 650,000
Long term debt, gross	274,817	290,431
Infrastructure Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 333,957
Infrastructure Loans \| Secured Borrowings \| SOFR
Secured Borrowings
Pricing margin	2.07%
Conduit Loans \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 375,000
Long term debt, gross	57,960	8,423
Conduit Loans \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 66,572
Conduit Loans \| Secured Borrowings \| SOFR
Secured Borrowings
Pricing margin	2.35%
CMBS/RMBS
Secured Borrowings
Coupon Rate	3.25%
Secured financing agreements, net	$ 261,800
Amount outstanding on a repurchase facility not subject to margin calls	261,800
Amount outstanding on repurchase facility	$ 42,200
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	$ 356,200
Rolling maturity period	11 months
Maturity period	12 months
CMBS/RMBS \| SOFR \| Weighted-average
Secured Borrowings
Coupon Rate	2.15%
CMBS/RMBS \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	$ 1,083,841
Long term debt, gross	824,912	840,625
CMBS/RMBS \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	1,488,626
Total Repurchase Agreements \| Secured Borrowings
Secured Borrowings
Maximum Facility Size	17,385,894
Long term debt, gross	10,944,178	$ 10,799,120
Total Repurchase Agreements \| Secured Borrowings \| Asset Pledged as Collateral
Secured Borrowings
Pledged Asset Carrying Value	$ 15,299,783

The amount outstanding on a repurchase facility

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

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Represents the minimum interest rate applicable to various debt instruments.

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

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- Definition

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

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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.

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

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

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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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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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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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Amount, after accumulated amortization, of debt discount (premium).

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Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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