Loans - Narrative (Details) $ in Thousands	3 Months Ended
Mar. 31, 2024 USD ($) loan Item	Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 19,627,876	$ 20,528,925
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 14,552,758
Number of loans modified \| loan	3
Amortized cost basis of loans modified	$ 650,800
Percentage of commercial loans amortized cost basis	4.50%
Infrastructure Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 2,385,750
Mortgage Loan \| Texas \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 252,000
Granted team extension period	28 months
Number of extension options \| Item	2
Extension term	1 year
Preferred equity commitment	$ 30,000
Unfunded commitments	22,900
Mortgage Loan \| ALABAMA \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 76,600
Decrease in interest rate	0.55%
Reduced interest rate period	24 months
Payments received from loan modifications	$ 3,400
Mortgage Loan \| ARIZONA \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	45,000
Interest not yet received	600
First Mortgage and Mezzanine \| Washington, DC \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 322,200
Granted team extension period	24 months
Decrease in interest rate	2.85%
First Mortgage and Mezzanine \| Washington, DC \| Commercial Portfolio Segment \| Floor Rate
Financing Receivable, Allowance for Credit Loss [Line Items]
Basis spread	5.00%
First Mortgage and Mezzanine \| Washington, DC \| Commercial Portfolio Segment \| SOFR
Financing Receivable, Allowance for Credit Loss [Line Items]
Basis spread	1.00%
Junior Mezzanine Loan \| Washington, DC \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	$ 18,200
Amount funded	6,400
Credit deteriorated \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	4,925
Credit deteriorated \| Senior Loans \| Chicago \| Infrastructure Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	4,900
90 days or greater past due \| Non-Credit Deterioration
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	427,900
90 days or greater past due \| Non-Credit Deterioration \| Residential Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	80,400
90 days or greater past due \| Non-Credit Deterioration \| Mortgage Loan \| VIRGINIA \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	125,100
90 days or greater past due \| Non-Credit Deterioration \| Mortgage Loan \| Washington, DC \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	123,900
90 days or greater past due \| Non-Credit Deterioration \| First Mortgage and Mezzanine \| TENNESSEE \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	51,500
90 days or greater past due \| Non-Credit Deterioration \| Leasehold Mortgage Loan \| California \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	37,800
90 days or greater past due \| Non-Credit Deterioration \| Senior Loans \| New York \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	9,200
Not 90 days or greater past due \| Non-Credit Deterioration \| Senior Loans \| New Jersey \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	185,400
Not 90 days or greater past due \| Non-Credit Deterioration \| Junior Mezzanine Loan \| Washington, DC \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Carrying value	6,400
Mortgage loans on real estate commitment	$ 18,200

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Financing Receivable, Modified, Extension Term

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Financing Receivable, Modified, Interest Not Received

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Financing Receivable, Modified, Interest Rate Increase (Decrease)

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Financing Receivable, Modified, Number Of Extension Options

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Financing Receivable, Modified, Number Of Loans

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- Definition

Mortgage Loans on Real Estate, Commitment

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The gross carrying amount of the outstanding balance due under the mortgage loan.

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Mortgage Loans on Real Estate Gross Carrying Amount of Mortgages, Amount Funded

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Mortgage Loans on Real Estate Gross Carrying Amount of Mortgages, Modified

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Mortgage Loans on Real Estate Gross Carrying Amount of Mortgages, Modified, Percentage

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Mortgage Loans on Real Estate Preferred Equity Commitment

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Proceeds Received From Financing Receivable Modifications

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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