Funded amount, before allowance for credit loss, of financing receivable.

No definition available.

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- Definition

Funded and unfunded amount, before allowance for credit loss, of financing receivable.

+ References

No definition available.

+ Details

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- Definition

Represents the weighted average First Dollar LTV Ratio that is calculated by comparing the total of the company's senior most dollar and all senior lien positions within the capital stack to the fair value of the underlying collateral to determine the point at which the company will absorb a total loss of its position.

+ References

No definition available.

+ Details

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- Definition

Represents the weighted average loan to value ratio that is calculated by comparing the total of the carrying value of the company's loan and all senior lien positions within the capital stack to the fair value of the underlying collateral to determine the point at which the company will initially absorb a loss.

+ References

No definition available.

+ Details

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- Definition

Represents a category of loans on real estate expressed as a percentage of total loans on real estate.

+ References

No definition available.

+ Details

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- Definition

Represents the weighted average remaining maturity period of mortgage loans.

+ References

No definition available.

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- Definition

Represents the number of loans related to the real estate property under the loan portfolio.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents the number of unrelated borrowers.

+ References

No definition available.

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Balance Type:	na
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- Definition

Amount before allowance of loans and leases held in portfolio of transfer from Structured Business to Agency Business.

+ References

No definition available.

+ Details

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- Definition

Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate transfer from Structured Business to Agency Business.

+ References

No definition available.

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- Definition

Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column B
-Subsection 29

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-Publisher FASB
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-Section S99
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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

No definition available.

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Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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-Paragraph 1
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Loans and Investments - Investment Portfolio and Concentration of Credit Risk (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($) borrower loan	Dec. 31, 2020 USD ($) loan borrower	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)
Loans and Investments
Loans and investments, gross	$ 9,169,007,000	$ 5,475,082,000
Allowance for credit losses	(131,534,000)	(148,329,000)	$ (138,447,000)		$ (146,745,000)	$ (152,811,000)
Unearned revenue	(43,683,000)	(40,885,000)
Loans and investments, net	$ 8,993,790,000	$ 5,285,868,000
Percent of Total	100.00%	100.00%
Loan Count \| loan	476	328
Wtd. Avg. Pay Rate (as a percent)	4.56%	5.23%
Wtd. Avg. Remaining Months to Maturity	22 months	19 months 6 days
Wtd. Avg. First Dollar LTV Ratio (as percent)	2.00%	4.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	76.00%	77.00%
Credit risk concentration
Loans and Investments
Wtd. Avg. First Dollar LTV Ratio (as percent)	2.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	76.00%
Credit risk concentration \| Single-Family Rental
Loans and Investments
Percent of Total	3.00%
Wtd. Avg. First Dollar LTV Ratio (as percent)	0.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	63.00%
Total assets \| Credit risk concentration
Loans and Investments
Loan Count \| loan	32	22
Number of different borrowers \| borrower	5	5
Total assets \| Credit risk concentration \| Five Borrowers
Loans and Investments
Concentration risk, percentage	11.00%	12.00%
Bridge loans
Loans and Investments
Loans and investments, gross	$ 8,696,486,000	$ 5,022,509,000
Percent of Total	95.00%	92.00%
Loan Count \| loan	423	263
Wtd. Avg. Pay Rate (as a percent)	4.45%	5.09%
Wtd. Avg. Remaining Months to Maturity	20 months 21 days	16 months 6 days
Wtd. Avg. First Dollar LTV Ratio (as percent)	0.00%	0.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	76.00%	76.00%
Bridge loans \| Single-Family Rental
Loans and Investments
Number of loans under the loan portfolio \| loan	86	38
Total loan commitment	$ 614,300,000	$ 309,200,000
Preferred equity investments
Loans and Investments
Loans and investments, gross	$ 186,705,000	$ 159,242,000
Percent of Total	2.00%	3.00%
Loan Count \| loan	13	29
Wtd. Avg. Pay Rate (as a percent)	6.62%	7.40%
Wtd. Avg. Remaining Months to Maturity	35 months 6 days	45 months
Wtd. Avg. First Dollar LTV Ratio (as percent)	59.00%	32.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	89.00%	82.00%
Mezzanine loans
Loans and Investments
Loans and investments, gross	$ 256,413,000	$ 224,928,000
Percent of Total	3.00%	4.00%
Loan Count \| loan	38	14
Wtd. Avg. Pay Rate (as a percent)	6.83%	7.07%
Wtd. Avg. Remaining Months to Maturity	53 months 15 days	49 months 24 days
Wtd. Avg. First Dollar LTV Ratio (as percent)	30.00%	64.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	82.00%	89.00%
Other loans
Loans and Investments
Loans and investments, gross	$ 29,403,000	$ 68,403,000
Percent of Total	1.00%	1.00%
Loan Count \| loan	2	22
Wtd. Avg. Pay Rate (as a percent)	4.63%	4.95%
Wtd. Avg. Remaining Months to Maturity	51 months 3 days	74 months 24 days
Wtd. Avg. First Dollar LTV Ratio (as percent)	0.00%	0.00%
Wtd. Avg. Last Dollar LTV Ratio (as percent)	69.00%	69.00%
Other loans \| Single-Family Rental
Loans and Investments
Number of loans under the loan portfolio \| loan	2	22
Unpaid principal balance, funded	$ 277,300,000	$ 88,100,000
Transfer of fixed rate SFR from Structured Business to Agency Business				$ 21
Transfer of UPB from Structured Business To Agency Business				$ 65,200,000