FS Credit Real Estate Income Trust (FSREI) 10-Q 15 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Nov. 08, 2021
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Entity Registrant Name	FS Credit Real Estate Income Trust, Inc.
Entity Central Index Key	0001690536
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	000-56163
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	81-4446064
Entity Address, Address Line One	201 Rouse Boulevard
Entity Address, City or Town	Philadelphia
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19112
City Area Code	215
Local Phone Number	495-1150
Common Class F [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		898,133
Common Class Y [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		906,648
Common Class T [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		1,370,351
Common Class S [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		19,875,415
Common Class D [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		631,545
Common Class M [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		2,707,225
Common Class I [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		10,436,693

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents		$ 99,839	$ 15,707
Restricted cash		5,475	2,167
Loans receivable, held-for-investment		2,511,901	700,149
Mortgage-backed securities held-to-maturity		37,723	37,314
Mortgage-backed securities available-for-sale, at fair value		48,737	0
Reimbursement due from sponsor		0	444
Interest receivable		5,699	3,170
Deferred financing costs		2,761	152
Other assets		65	15,876
Total assets	[1]	2,712,200	774,979
Liabilities
Collateralized loan obligations (net of deferred financing costs of $10,166 and $4,556, respectively)		964,434	323,109
Repurchase agreements payable (net of deferred financing costs of $2,073 and $194, respectively)		906,010	125,266
Credit facility payable		40,000
Due to related party		36,131	15,481
Interest payable		1,307	344
Payable for shares repurchased		2,068	1,530
Other liabilities		19,454	3,537
Total liabilities	[1]	1,969,404	469,267
Commitments and contingencies (See Note 10)
Stockholders' equity
Preferred stock, $0.01 par value, 50,000,000 shares authorized, 125 and 0 issued and outstanding, respectively
Additional paid-in capital		740,453	303,783
Accumulated other comprehensive income (loss)		104
Retained earnings		1,928	1,802
Total stockholders' equity		742,796	305,712
Total liabilities and stockholders' equity		2,712,200	774,979
Common Class F [Member]
Stockholders' equity
Common stock, value		9	9
Total stockholders' equity		9	9
Common Class Y [Member]
Stockholders' equity
Common stock, value		9	1
Total stockholders' equity		9	1
Common Class T [Member]
Stockholders' equity
Common stock, value		13	12
Total stockholders' equity		13	12
Common Class S [Member]
Stockholders' equity
Common stock, value		162	58
Total stockholders' equity		162	58
Common Class D [Member]
Stockholders' equity
Common stock, value		6	5
Total stockholders' equity		6	5
Common Class M [Member]
Stockholders' equity
Common stock, value		28	20
Total stockholders' equity		28	20
Common Class I [Member]
Stockholders' equity
Common stock, value		84	22
Total stockholders' equity		$ 84	$ 22
[1]	The September 30, 2021 and December 31, 2020 consolidated balance sheets include assets of consolidated variable interest entities, or VIEs, that can only be used to settle obligations of the VIEs, and liabilities of consolidated VIEs for which creditors do not have recourse to the Company. As of September 30, 2021 and December 31, 2020, assets of the VIEs totaled $1,212,364 and $429,771, respectively, and liabilities of the VIEs totaled $965,277 and $323,336, respectively. See Note 9 to the unaudited consolidated financial statements for further details.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Deferred financing costs		$ 2,761	$ 152
Preferred stock, par value		$ 0.01	$ 0.01
Preferred stock, shares authorized		50,000,000	50,000,000
Preferred stock, shares issued		125	0
Preferred stock, shares outstanding		125	0
VIEs Assets	[1]	$ 2,712,200	$ 774,979
VIEs Liabilities	[1]	1,969,404	469,267
Variable Interest Entity, Primary Beneficiary [Member]
VIEs Assets		1,212,364	429,771
VIEs Liabilities		965,277	323,336
Repurchase agreements payable [Member]
Deferred financing costs		2,073	194
Collateralized Loan Obligations [Member]
Deferred financing costs		$ 10,166	$ 4,556
Common Class F [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		895,749	912,469
Common stock, shares outstanding		895,749	912,469
Common Class Y [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		906,648	137,116
Common stock, shares outstanding		906,648	137,116
Common Class T [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		1,340,710	1,245,658
Common stock, shares outstanding		1,340,710	1,245,658
Common Class S [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		16,209,558	5,778,640
Common stock, shares outstanding		16,209,558	5,778,640
Common Class D [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		619,957	546,298
Common stock, shares outstanding		619,957	546,298
Common Class M [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		2,804,634	1,971,039
Common stock, shares outstanding		2,804,634	1,971,039
Common Class I [Member]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		300,000,000	300,000,000
Common stock, shares issued		8,405,129	2,171,528
Common stock, shares outstanding		8,405,129	2,171,528
[1]	The September 30, 2021 and December 31, 2020 consolidated balance sheets include assets of consolidated variable interest entities, or VIEs, that can only be used to settle obligations of the VIEs, and liabilities of consolidated VIEs for which creditors do not have recourse to the Company. As of September 30, 2021 and December 31, 2020, assets of the VIEs totaled $1,212,364 and $429,771, respectively, and liabilities of the VIEs totaled $965,277 and $323,336, respectively. See Note 9 to the unaudited consolidated financial statements for further details.

Unaudited Consolidated Statemen

Unaudited Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net interest income
Interest income	$ 23,676	$ 10,270	$ 51,431	$ 28,004
Less: Interest expense	(7,929)	(2,733)	(15,739)	(8,940)
Net interest income	15,747	7,537	35,692	19,064
Other expenses
Management and performance fees	1,956	1,225	5,237	2,979
General and administrative expenses	2,713	1,456	5,512	3,353
Less: Expense limitation		(397)	(56)	(579)
Add: Expense recoupment to sponsor	8		398
Net other expenses	4,677	2,284	11,091	5,753
Other income (loss)
Net realized gain (loss) on mortgage-backed securities available-for-sale		(556)		(556)
Total other income (loss)		(556)		(556)
Net income	11,070	4,697	24,601	12,755
Preferred stock dividends	(3)	(3)	(11)	(10)
Net income attributable to FS Credit Real Estate Income Trust, Inc.	$ 11,067	$ 4,694	$ 24,590	$ 12,745
Per share information—basic and diluted
Net income per share of common stock (earnings per share)	$ 0.41	$ 0.44	$ 1.23	$ 1.28
Weighted average common stock outstanding	26,824,393	10,629,214	20,023,193	9,923,479

Unaudited Consolidated Statem_2

Unaudited Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net income	$ 11,070	$ 4,697	$ 24,601	$ 12,755
Other comprehensive income
Net change in unrealized gain (loss) on mortgage-backed securities available-for-sale	24	1,064	104	(17)
Total other comprehensive income (loss)	24	1,064	104	(17)
Comprehensive income	$ 11,094	$ 5,761	$ 24,705	$ 12,738

Unaudited Consolidated Statem_3

Unaudited Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Class F [Member]	Common Class Y [Member]	Common Class T [Member]	Common Class S [Member]	Common Class D [Member]	Common Class M [Member]	Common Class I [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings (Accumulated Deficit) [Member]
Balance at beginning of period, amount at Dec. 31, 2019	$ 165,787	$ 15	$ 1	$ 10	$ 14	$ 3	$ 14	$ 12	$ 165,082	$ 17	$ 619
Common stock issued	137,348			2	34	3	6	10	137,293
Preferred stock issued	125								125
Distributions declared	(11,699)										(11,699)
Proceeds from distribution reinvestment plan	3,706								3,706
Redemptions of common stock	(38,184)	(6)			(3)		(2)	(4)	(38,169)
Stockholder servicing fees	(7,471)								(7,471)
Net income	12,755										12,755
Dividends on preferred stock	(10)										(10)
Other comprehensive income	(17)									(17)
Balance at end of period, amount at Sep. 30, 2020	262,340	9	1	12	45	6	18	18	260,566	0	1,665
Balance at beginning of period, amount at Jun. 30, 2020	240,411	9	1	12	41	5	17	15	240,127	(1,064)	1,248
Common stock issued	23,393				5		1	3	23,383
Distributions declared	(4,277)										(4,277)
Proceeds from distribution reinvestment plan	1,365								1,365
Redemptions of common stock	(3,338)				(1)		0	0	(3,337)
Stockholder servicing fees	(972)								(972)
Net income	4,697										4,697
Dividends on preferred stock	(3)										(3)
Other comprehensive income	1,064									1,064
Balance at end of period, amount at Sep. 30, 2020	262,340	9	1	12	45	6	18	18	260,566	0	1,665
Balance at beginning of period, amount at Dec. 31, 2020	305,712	9	1	12	58	5	20	22	303,783		1,802
Common stock issued	460,045		9	1	103	1	9	61	459,861
Distributions declared	(24,464)										(24,464)
Proceeds from distribution reinvestment plan	9,603				2			2	9,599
Redemptions of common stock	(9,354)		(1)		(1)		(1)	(1)	(9,350)
Stockholder servicing fees	(22,399)								(22,399)
Offering costs	(1,041)								(1,041)
Net income	24,601										24,601
Dividends on preferred stock	(11)										(11)
Other comprehensive income	104									104
Balance at end of period, amount at Sep. 30, 2021	742,796	9	9	13	162	6	28	84	740,453	104	1,928
Balance at beginning of period, amount at Jun. 30, 2021	483,487	9	9	13	101	6	24	41	481,390	80	1,814
Common stock issued	272,129				61		4	44	272,020
Distributions declared	(10,953)										(10,953)
Proceeds from distribution reinvestment plan	4,448				1				4,447
Redemptions of common stock	(4,121)				(1)			(1)	(4,119)
Stockholder servicing fees	(12,923)								(12,923)
Offering costs	(362)								(362)
Net income	11,070										11,070
Dividends on preferred stock	(3)										(3)
Other comprehensive income	24									24
Balance at end of period, amount at Sep. 30, 2021	$ 742,796	$ 9	$ 9	$ 13	$ 162	$ 6	$ 28	$ 84	$ 740,453	$ 104	$ 1,928

Unaudited Consolidated Statem_4

Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Net income	$ 24,601	$ 12,755
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Amortization of deferred fees on loans and debt securities	(1,111)	(761)
Amortization of deferred financing costs	2,684	1,842
Net realized loss on sale of mortgage-backed securities available-for-sale		556
Changes in assets and liabilities
Reimbursement due from sponsor	444	103
Interest receivable	(2,529)	(1,566)
Other assets	89	5,149
Due to related party	9	6,614
Interest payable	963	(425)
Other liabilities	2,441	(5,274)
Net cash provided by (used in) operating activities	27,591	18,993
Cash flows used in investing activities
Origination and fundings of loans receivable	(1,990,205)	(214,855)
Principal collections from loans receivable, held-for-investment	169,753	12,617
Proceeds from sale of loans receivable, held-for-sale	24,397
Exit and extension fees received on loans receivable, held-for-investment	727	167
Purchases of mortgage-backed securities available-for-sale	(36,576)	(25,555)
Principal repayments of mortgage-backed securities		31,633
Purchases of mortgage-backed securities held-to-maturity		(37,004)
Net cash used in investing activities	(1,831,904)	(232,997)
Cash flows from financing activities
Issuance of common stock	460,045	137,348
Redemptions of common stock	(8,816)	(36,949)
Stockholder distributions paid	(13,453)	(7,651)
Stockholder servicing fees	(1,758)	(857)
Offering costs paid	(1,041)	0
Borrowings under repurchase agreements	1,433,000	126,590
Repayments under repurchase agreements	(650,377)	(21,417)
Borrowings under credit facility	256,000	6,000
Repayments under credit facility	(216,000)	(6,000)
Proceeds from issuance of collateralized loan obligation	646,935
Payment of deferred financing costs	(12,782)	(1,184)
Proceeds from issuance of preferred stock		125
Net cash provided by (used in) financing activities	1,891,753	196,005
Total increase (decrease) in cash, cash equivalents and restricted cash	87,440	(17,999)
Cash, cash equivalents and restricted cash at beginning of period	17,874	78,155
Cash, cash equivalents and restricted cash at end of period	105,314	60,156
Supplemental disclosure of cash flow information and non-cash financial activities
Payments of interest	12,092	7,523
Accrued stockholder servicing fee	20,641	6,614
Distributions payable	2,530	1,011
Reinvestment of stockholder distributions	9,603	3,706
Payable for shares repurchased	$ 2,068	1,297
Loan principal payments held by servicer		$ 10,381

Principal Business and Organiza

Principal Business and Organization	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principal Business and Organization	Note 1. Principal Business and Organization FS Credit Real Estate Income Trust, Inc., or the Company, was incorporated under the general corporation laws of the State of Maryland on November 7, 2016 and formally commenced investment operations on September 13, 2017. The Company is currently conducting a public offering of up to $2,750,000 of its Class T, Class S, Class D, Class M and Class I shares of common stock pursuant to a registration statement on Form S-11 The Company also previously conducted private offerings of its Class F common stock and Class Y common stock. The Company is managed by FS Real Estate Advisor, LLC, or FS Real Estate Advisor, a subsidiary of the Company’s sponsor, Franklin Square Holdings, L.P., which does business as FS Investments, or FS Investments, a national sponsor of alternative investment funds designed for the individual investor. FS Real Estate Advisor has engaged Rialto Capital Management, LLC, or Rialto, to act as its sub-adviser. The Company has elected to be taxed as a real estate investment trust, or REIT, for U.S. federal income tax purposes commencing with its taxable year ended December 31, 2017. The Company intends to be an investment vehicle of indefinite duration focused on real estate debt investments and other real estate-related assets. The shares of common stock are generally intended to be sold and repurchased by the Company on a continuous basis. The Company intends to conduct its operations so that it is not required to register under the Investment Company Act of 1940, as amended, or the 1940 Act. The Company’s primary investment objectives are to: provide current income in the form of regular, stable cash distributions to achieve an attractive dividend yield; preserve and protect invested capital; realize appreciation in net asset value, or NAV, from proactive investment management and asset management; and provide an investment alternative for stockholders seeking to allocate a portion of their long-term investment portfolios to commercial real estate debt with lower volatility than public real estate companies.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Basis of Presentation: eliminated nature necessary statement Use of Estimates: Principles of Consolidation: The Company consolidates VIEs in which it is considered to be the primary beneficiary. The primary beneficiary is defined as the entity having both of the following characteristics: (1) the power to direct the activities that, when taken together, most significantly impact the VIE’s performance; and (2) the obligation to absorb losses and right to receive the returns from the VIE that would be significant to the VIE. The Company determines whether it is the primary beneficiary of an entity subject to consolidation based on a qualitative assessment of the VIE’s capital structure, contractual terms, nature of the VIE’s operations and purpose and the Company’s relative exposure to the related risks of the VIE on the date it becomes initially involved in the VIE. The Company reassesses its VIE determination with respect to an entity on an ongoing basis. Cash, Cash Equivalents and Restricted Cash: The following table provides a reconciliation of cash, cash equivalents and restricted cash in the Company’s consolidated balance sheets to the total amount shown in the Company’s unaudited consolidated statements of cash flows: September 30, 2021 2020 Cash and cash equivalents $ 99,839 $ 57,840 Restricted cash 5,475 2,316 Total cash, cash equivalents and restricted cash $ 105,314 $ 60,156 Loans Receivable and Provision for Loan Losses: Loans that the Company originates or purchases that the Company is unable to hold, or intends to sell or otherwise dispose of, in the foreseeable future are classified as held-for-sale FS Real Estate Advisor and Rialto perform a quarterly review of the Company’s portfolio of loans. In connection with this review, FS Real Estate Advisor and Rialto assess the risk factors of each loan and assign a risk rating based on a variety of factors, including, without limitation, loan-to-value 5-point Loan Risk Rating Summary Description 1 Very Low Risk 2 Low Risk 3 Medium Risk 4 High Risk/Potential for Loss: A loan that has a risk of realizing a principal loss 5 Impaired/Loss Likely: A loan that has a very high risk of realizing a principal loss or has otherwise incurred a principal loss Mortgage-backed Securities: held-to-maturity available-for-sale held-to-maturity Held-to-maturity available-for The Company regularly monitors its mortgage-backed securities to ensure investments that may be other-than-temporarily impaired are timely identified, properly valued and charged against earnings in the proper period. The determination that a security has incurred an other-than-temporary decline in value requires the judgment of management. Assessment factors include, but are not limited to, the length of time and the extent to which the market value has been less than amortized cost, the financial condition and rating of the issuer, and the intent to sell or whether it is more likely than not that the Company will be required to sell. Fair Value of Financial Instruments: Fair Value Measurements and Disclosures ASC Topic 820 also establishes a fair value hierarchy that prioritizes and ranks the level of market price observability used in measuring financial instruments. Market price observability is affected by a number of factors, including the type of financial instrument, the characteristics specific to the financial instrument, and the state of the marketplace, including the existence and transparency of transactions between market participants. Financial instruments with readily available quoted prices in active markets generally will have a higher degree of market price observability and a lesser degree of judgment used in measuring fair value. Financial instruments measured and reported at fair value are classified and disclosed based on the observability of inputs used in the determination, as follows: Level 1: Generally includes only unadjusted quoted prices that are available in active markets for identical financial instruments as of the reporting date. Level 2: Pricing inputs include quoted prices in active markets for similar instruments, quoted prices in less active or inactive markets for identical or similar instruments where multiple price quotes can be obtained, and other observable inputs, such as interest rates, yield curves, credit risks, and default rates. Level 3: Pricing inputs are unobservable for the financial instruments and include situations where there is little, if any, market activity for the financial instrument. These inputs require significant judgment or estimation by management or third parties when determining fair value and generally represent anything that does not meet the criteria of Levels 1 and 2. The estimated value of each asset reported at fair value using Level 3 inputs is determined by an internal committee composed of members of senior management of FS Real Estate Advisor. Certain of the Company’s assets are reported at fair value either (i) on a recurring basis, as of each quarter-end, The Company is also required by GAAP to disclose fair value information about financial instruments that are not otherwise reported at fair value in the Company’s consolidated balance sheets, to the extent it is practicable to estimate a fair value for those instruments. These disclosure requirements exclude certain financial instruments and all non-financial The following methods and assumptions are used to estimate the fair value of each class of financial instruments, for which it is practicable to estimate that value: • Cash and cash equivalents: The carrying amount of cash on deposit and in money market funds approximates fair value. • Restricted cash: The carrying amount of restricted cash approximates fair value. • Loans receivable, net: The fair values for these loans were estimated by FS Real Estate Advisor based on discounted cash flow methodology taking into consideration factors, including capitalization rates, discount rates, leasing, occupancy rates, availability and cost of financing, exit plan, sponsorship, actions of other lenders, and indications of market value from other market participants. • Mortgage-backed securities available-for-sale: • Mortgage-backed securities held-to-maturity: • Collateralized loan obligations, repurchase obligations and credit facility: The fair values for these instruments were estimated based on the rate at which similar credit facilities would have currently been priced. Deferred Financing Costs: costs Revenue Recognition: ex-dividend Loans are considered past due when payments are not made in accordance with the contractual terms. The Company does not accrue as receivable interest on loans if it is not probable that such income will be collected. Loans are placed on non-accrual non-accrual non-performing Organization Costs: other Offering Costs: paid-in Income Taxes: Uncertainty in Income Taxes expense Stockholder Servicing Fees: follows Liabilities paid-in Recent Accounting Pronouncements: 2016-13, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments (Topic 326) 2016-13. 2016-13 2016-13 available-for-sale 2019-10, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instrument (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) Effective Dates, 2016-13

Loans Receivable

Loans Receivable	9 Months Ended
	Sep. 30, 2021
Receivables [Abstract]
Loans Receivable	Note 3. Loans Receivable The following table details overall statistics for the Company’s loans receivable portfolio as of September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Number of loans 78 35 Principal balance $ 2,511,999 $ 699,250 Net book value $ 2,511,901 $ 700,149 Unfunded loan commitments (1) $ 185,674 $ 100,389 Weighted-average cash coupon (2) L+3.54 % L+4.25 % Weighted-average all-in (2) L+3.58 % L+4.35 % Weighted-average maximum maturity (years) (3) 4.4 3.7 (1) The Company may be required to provide funding when requested by the borrower in accordance with the terms of the underlying agreements. (2) The Company’s floating-rate loans are indexed to the London Interbank Offered Rate, or LIBOR. In addition to cash coupon, all-in (3) Maximum maturity assumes all extension options are exercised by the borrower; however, loans may be repaid prior to such date. For the nine months ended September 30, 2021 and 2020, the activity in the Company’s loan portfolio, was as follows: For the Nine Months Ended September 30, 2021 2020 Balance at beginning of period $ 700,149 $ 406,645 Loan fundings 1,990,205 214,855 Loan repayments (178,428 ) (22,988 ) Amortization of deferred fees on loans 702 680 Exit and extension fees received on loans (727 ) (167 ) Balance at end of period $ 2,511,901 $ 599,015 The following tables detail the property type and geographic location of the properties securing the loans in the Company’s loans receivable, held-for-investment September 30, 2021 (Unaudited) December 31, 2020 Property Type Net Book Value Percentage Net Book Value Percentage Office $ 292,375 12 % $ 174,483 25 % Industrial 305,172 12 % 168,876 24 % Multifamily 1,518,516 60 % 130,648 19 % Mixed Use 112,578 4 % 91,556 13 % Hospitality 63,422 3 % 62,759 9 % Retail 55,283 2 % 52,128 7 % Self Storage 164,555 7 % 19,699 3 % Total $ 2,511,901 100 % $ 700,149 100 % September 30, 2021 (Unaudited) December 31, 2020 Geographic Location (1) Net Book Value Percentage Net Book Value Percentage South $ 1,400,387 56 % $ 311,123 44 % West 475,730 19 % 201,318 29 % Northeast 394,132 15 % 168,009 24 % Midwest 221,952 9 % — — Various 19,700 1 % 19,699 3 % Total $ 2,511,901 100 % $ 700,149 100 % (1) As defined by the United States Department of Commerce, Bureau of the Census. Loan Risk Rating As further described in Note 2, FS Real Estate Advisor and Rialto assess the risk factors of each loan and assign a risk rating based on a variety of factors, including, without limitation, loan-to-value 5-point The following table allocates the net book value of the Company’s loans receivable, held-for-investment September 30, 2021 (Unaudited) December 31, 2020 Risk Rating Number of Net Book Percentage Number of Net Book Percentage 1 — $ — — — $ — — 2 — — — — — — 3 78 2,511,901 100 % 34 689,104 98 % 4 — — — 1 11,045 2 % 5 — — — — — — Total 78 $ 2,511,901 100 % 35 $ 700,149 100 % The Company did not have any impaired loans, non-accrual held-to-maturity

Mortgage Backed Securities

Mortgage Backed Securities	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Mortgage Backed Securities	Note 4. Mortgage Backed Securities Mortgage-backed securities, available-for-sale Commercial mortgage-backed securities, or CMBS, classified as available-for-sale The table below summarizes various attributes of the Company’s investments in available-for-sale Gross Unrealized Weighted Average Outstanding Face Amortized Gains Losses Fair Coupon Remaining September 30, 2021 (Unaudited) CMBS, available-for-sale $ 48,664 $ 48,633 $ 137 $ (33 ) $ 48,737 6.47 % 16.2 December 31, 2020 CMBS, available-for-sale $ — $ — $ — $ — $ — — % — Mortgage-backed securities, held-to-maturity The table below summarizes various attributes of the Company’s investments in held-to-maturity Net Carrying Gross Gross Fair Value September 30, 2021 (Unaudited) CMBS, held-to-maturity $ 37,723 — — $ 37,723 December 31, 2020 CMBS, held-to-maturity $ 37,314 — — $ 37,314 The table below summarizes the maturities of the Company’s investments in held-to-maturity Total Less than 1 year 1-3 years 3-5 years More than 5 years CMBS, held-to-maturity $ 37,723 — — $ 37,723 —

Financing Arrangements

Financing Arrangements	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Financing Arrangements	Note 5. Financing Arrangements The following tables present summary information with respect to the Company’s outstanding financing arrangements as of September 30, 2021 and December 31, 2020. For additional information regarding these financing arrangements, see the notes to the Company’s audited consolidated financial statements contained in its annual report on Form 10-K As of September 30, 2021 (Unaudited) Arrangement (1) Rate Amount Amount Maturity Date Carrying Fair Value Collateralized Loan Obligations 2019-FL1 L+1.20% — 2.50% (2) $ 327,665 $ — December 18, 2036 (3) $ 422,345 $ 423,079 2021-FL2 L+1.22% — 3.45% (2) 646,935 — May 5, 2038 (4) 782,595 784,983 974,600 — 1,204,940 1,208,062 Repurchase Agreements WF-1 L+2.15% — 2.50% (5) 314,092 35,908 August 30, 2022 392,642 392,816 GS-1 L+1.75% — 2.75% (6) 151,257 23,743 January 26, 2022 190,981 191,025 BB-1 L+1.55% — 1.95% 416,803 33,197 February 22, 2024 520,745 521,125 RBC Facility L+1.35% 25,931 — N/A 36,580 36,683 908,083 92,848 1,140,948 1,141,649 Revolving Credit Facility CNB Facility L+2.25% (7) 40,000 15,000 June 7, 2023 — — MM-1 L+2.10% (2) — 200,000 September 20, 2029 — — 40,000 215,000 — — Total $ 1,922,683 $ 307,848 $ 2,345,888 $ 2,349,711 As of December 31, 2020 Arrangement (1) Rate Amount Amount Maturity Date Carrying Fair Value Collateralized Loan Obligation 2019-FL1 L+1.20% — 2.50% (2) $ 327,665 $ — December 18, 2036 (3) $ 411,455 $ 409,497 Repurchase Agreements WF-1 L+2.15% — 2.50% (5) 29,889 70,111 August 30, 2021 39,945 39,977 GS-1 L+1.75% — 2.75% (6) 95,571 79,429 January 26, 2021 127,512 126,995 125,460 149,540 167,457 166,972 Revolving Credit Facility CNB Facility L+2.25% (2) — 25,000 August 23, 2022 — — Total $ 453,125 $ 174,540 $ 578,912 $ 576,469 (1) The carrying amount outstanding under the facilities approximates their fair value. (2) LIBOR is subject to a 0.00% floor. (3) The 2019-FL1 2019-FL1 (4) The 2021-FL2 2021-FL2 (5) LIBOR is subject to a 0.00% floor. WF-1 (6) LIBOR is subject to a 0.50% floor. GS-1 and (7) LIBOR is subject to a 0.50% floor. The Company’s average borrowings and weighted average interest rate, including the effect of non-usage non-usage Under its financing arrangements, the Company has made certain representations and warranties and is required to comply with various covenants, reporting requirements and other customary requirements for similar financing arrangements. The Company was in compliance with all covenants required by its financing arrangements as of September 30, 2021 and December 31, 2020. 2019-FL1 On December 5, 2019, the Company issued $327,665 of collateralized loan obligation notes, or the CLO1 Transaction, through FS Rialto Sub-REIT Sub-REIT, Sub-REIT, 2019-FL1 2019-FL1 Co-Issuer, as co-issuer, Co-Issuer and, As of September 30, 2021, the 2019-FL1 20 The Company incurred issuance costs which are amortized over the remaining life of the loans that collateralized the 2019-FL1 2021-FL2 On May 5, 2021, the Company issued $646,935 of collateralized loan obligation notes, or the CLO2 Transaction, through the Sub-REIT Sub-REIT, 2021-FL2 2021-FL2 Co-Issuer, co-issuer, Co-Issuer As of September 30, 2021, the 2021-FL2 The Company incurred issuance costs which are amortized over the remaining life of the loans that collateralized the 2021-FL2 WF-1 On August 30, 2017, the Company’s indirect wholly owned, special-purpose financing subsidiary, WF-1, WF-1 WF-1 WF-1 WF-1 On July 6, 2021, WF-1 WF-1 one three one-year The Company incurred deferred financing costs related to the WF-1 GS-1 On January 26, 2018, the Company’s indirect wholly-owned, special-purpose financing subsidiary, GS-1, GS-1 GS-1 origination of whole, performing senior commercial or multifamily floating-rate mortgage loans secured by first liens on office, retail, industrial, hospitality, multifamily or other commercial properties. The maximum amount of financing available under the GS-1 GS-1 The initial availability period of the GS-1 GS-1 GS-1 GS-1 GS-1 one-year GS-1 GS-1 The Company incurred deferred financing costs related to the GS-1 BB-1 On February 22, 2021, the Company’s indirect wholly owned, special-purpose financing subsidiary, FS CREIT Finance BB-1 BB-1, BB-1 BB-1 BB-1 BB-1, BB-1 the BB-1 Facility was amended BB-1 BB-1 BB-1 The initial availability period of the BB-1 BB-1 BB-1 one-year BB-1 one BB-1 BB-1 The Company incurred deferred financing costs related to the BB-1 RBC Facility On March 2, 2020, FS CREIT Investments LLC, the Company’s wholly-owned subsidiary, or FS CREIT Investments, as seller, entered into a Master Repurchase Agreement, or the RBC Facility, with Royal Bank of Canada, as buyer, to enable FS CREIT Investments to execute repurchase transactions of securities and financial instruments on an asset-by-asset CNB Facility On August 22, 2019, the Company and FS CREIT Finance Holdings LLC, each as a borrower, entered into a Loan and Security Agreement, or the CNB Loan Agreement, and together with the related transaction documents, the CNB Facility, with City National Bank, or CNB, as administrative agent and lender. The maximum committed facility amount under the CNB Facility as of September 30, 2021 was $55,000. Borrowings under the CNB Facility are subject to compliance with a borrowing base calculated based on the Company’s stockholder subscriptions and certain cash and assets held directly by the Company. Borrowings under the CNB Facility accrue interest at a rate equal to LIBOR plus a spread of 2.25% per annum, and borrowed amounts must be repaid no later than 180 days after the funding date of such borrowing. In addition, the borrowers pay a non-utilization The Company incurred deferred financing costs related to the CNB Facility, which is being amortized to interest expense over the life of the facility. As of September 30, 2021, $458 of deferred financing costs had yet to be amortized to interest expense. MM-1 On September 20, 2021, FS CREIT Finance MM-1 MM-1, MM-1, MM-1 MM-1 Borrowings under the MM-1 Facility are subject to compliance with a borrowing base calculated based on advance rates applied to the value of MM-1’s assets. The maximum committed facility amount under the MM-1 LIBOR plus a spread of 2.10% per annum MM-1 MM-1 The Company incurred deferred financing costs related to the MM-1 facility, which is being amortized to interest expense over the life of the facility. As of September 30, 2021, $2,303 of deferred financing costs had yet to be amortized to interest expense.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Note 6. Related Party Transactions Compensation of FS Real Estate Advisor and the Dealer Manager Pursuant to the second amended and restated advisory agreement dated as of August 17, 2018, or the advisory agreement, FS Real Estate Advisor is entitled to a base management fee equal to 1.25% of the NAV for the Company’s Class T, Class S, Class D, Class M and Class I shares, payable quarterly in arrears. The payment of all or any portion of the base management fee accrued with respect to any quarter may be deferred by FS Real Estate Advisor, without interest, and may be taken in any such other quarter as FS Real Estate Advisor may determine. In calculating the Company’s base management fee, the Company will use its NAV before giving effect to accruals for such fee, stockholder servicing fees or distributions payable on its shares. The base management fee is a class-specific expense. No base management fee is paid on the Company’s Class F or Class Y shares. FS Real Estate Advisor is also entitled to the performance fee calculated and payable quarterly in arrears in an amount equal to 10.0% of the Company’s Core Earnings (as defined below) for the immediately preceding quarter, subject to a hurdle rate, expressed as a rate of return on average adjusted capital, equal to 1.625% per quarter, or an annualized hurdle rate of 6.5%. As a result, FS Real Estate Advisor does not earn a performance fee for any quarter until the Company’s Core Earnings for such quarter exceed the hurdle rate of 1.625%. For purposes of the performance fee, “adjusted capital” means cumulative net proceeds generated from sales of the Company’s common stock other than Class F common stock (including proceeds from the Company’s distribution reinvestment plan) reduced for distributions from non-liquidating “catch-up” For purposes of calculating the performance fee, “Core Earnings” means: the net income (loss) attributable to stockholders of Class Y, Class T, Class S, Class D, Class M and Class I shares, computed in accordance with GAAP (provided that net income (loss) attributable to Class Y stockholders shall be reduced by an amount equal to the base management fee that would have been paid if Class Y shares were subject to such fee), including realized gains (losses) not otherwise included in GAAP net income (loss) and excluding (i) non-cash non-cash (v) one-time non-cash FS Real Estate Advisor has engaged Rialto as sub-adviser sub-adviser’s sub-adviser The Company reimburses FS Real Estate Advisor and Rialto for their actual costs incurred in providing administrative services to the Company. FS Real Estate Advisor and Rialto are required to allocate the cost of such services to the Company based on objective factors such as total assets, revenues and/or time allocations. At least annually, the Company’s board of directors reviews the amount of the administrative services expenses reimbursable to FS Real Estate Advisor and Rialto to determine whether such amounts are reasonable in relation to the services provided. The Company will not reimburse FS Real Estate Advisor or Rialto for any services for which it receives a separate fee or for any administrative expenses allocated to employees to the extent they serve as executive officers of the Company. FS Investments funded the Company’s organization and offering costs in the amount of $15,472 for the period from November 7, 2016 (Inception) to September 30, 2021. These expenses include legal, accounting, printing, mailing and filing fees and expenses, due diligence expenses of participating broker-dealers supported by detailed and itemized invoices, costs in connection with preparing sales materials, design and website expenses, fees and expenses of the Company’s transfer agent, fees to attend retail seminars sponsored by participating broker-dealers and reimbursements for customary travel, lodging, and meals, but excluding selling commissions, dealer manager fees and stockholder servicing fees. Under the advisory agreement, FS Real Estate Advisor agreed to advance all of the Company’s organization and offering expenses on the Company’s behalf until it raised $250,000 of gross proceeds from its public offering. FS Real Estate Advisor and Rialto agreed to defer the recoupment of any organization and offering expenses that may be reimbursable by the Company under the advisory agreement with respect to gross proceeds raised in the offering in excess of $250,000 until FS Real Estate Advisor, in its sole discretion, determined that the Company had achieved economies of scale sufficient to ensure that it could bear a reasonable level of expenses in relation to its income. The Company began reimbursing FS Real Estate Advisor in September 2020 and, as such, FS Real Estate Advisor may be reimbursed for any organization and offering expenses that it or Rialto has incurred on the Company’s behalf, up to a cap of 0.75% of gross proceeds raised after such time. During the nine months ended September 30, 2021, the Company paid $1,041 to FS Real Estate Advisor for offering costs previously funded. As of September 30, 2021, $14,146 of offering expenses previously funded remained subject to reimbursement to FS Real Estate Advisor and Rialto. The following table describes the fees and expenses accrued under the advisory agreement during the three and nine months ended September 30, 2021 and 2020: Three Months Ended Nine Months Ended Related Party Source Agreement Description 2021 2020 2021 2020 FS Real Estate Advisor Advisory Agreement Base Management Fee (1) $ 1,944 $ 760 $ 4,269 $ 2,076 FS Real Estate Advisor Advisory Agreement Performance Fee (2) $ 8 $ 465 $ 968 903 FS Real Estate Advisor Advisory Agreement Administrative Services Expenses (3) $ 1,260 $ 810 $ 2,708 $ 1,698 (1) During the nine months ended September 30, 2021 and 2020, $3,194 and $1,642, respectively, in base management fees were paid to FS Real Estate Advisor. As of September 30, 2021 and December 31, 2020 and $869, respectively, (2) During the nine months ended September 30, 2021 and 2020, $1,276 and $438, respectively, in performance fees were paid to FS Real Estate Advisor. As of September 30, 2021 and December 31, 2020, $8 and $316, respectively, (3) During the nine months ended September 30, 2021 and 2020, $2,448 and $1,610, respectively, of the accrued administrative services expenses related to the allocation of costs of administrative personnel for services rendered to the Company by FS Real Estate Advisor and Rialto and the remainder related to other reimbursable expenses. These amounts are recorded as general and administrative expenses on the accompanying unaudited consolidated statements of operations. The dealer manager for the Company’s continuous public offering is FS Investment Solutions, LLC, or FS Investment Solutions, which is an affiliate of FS Real Estate Advisor. Under the amended and restated dealer manager agreement dated as of August 17, 2018, or the dealer manager agreement, FS Investment Solutions is entitled to receive upfront selling commissions of up to 3.0%, and upfront dealer manager fees of 0.5% of the transaction price of each Class T share sold in the primary offering, however such amounts may vary at certain participating broker-dealers provided that the sum will not exceed 3.5% of the transaction price (subject to reductions for certain categories of purchasers). FS Investment Solutions is entitled to receive upfront selling commissions of up to 3.5% of the transaction price per Class S share sold in the primary offering (subject to reductions for certain categories of purchasers). The dealer manager anticipates that all of the selling commissions and dealer manager fees will be re-allowed No selling commissions or dealer manager fees are payable on the sale of Class D, Class M, Class I, Class F or Class Y shares or on shares of any class sold pursuant to the Company’s distribution reinvestment plan. Subject to the limitations described below, the Company pays FS Investment Solutions stockholder servicing fees for ongoing services rendered to stockholders by participating broker-dealers or by broker-dealers servicing investors’ accounts, referred to as servicing broker-dealers: • with respect to the Company’s outstanding Class T shares equal to 0.85% per annum of the aggregate NAV of its outstanding Class T shares, consisting of an advisor stockholder servicing fee of 0.65% per annum and a dealer stockholder servicing fee of 0.20% per annum; however, with respect to Class T shares sold through certain participating broker-dealers, the advisor stockholder servicing fee and the dealer stockholder servicing fee may be other amounts, provided that the sum of such fees will always equal 0.85% per annum of the NAV of such shares; • with respect to the Company’s outstanding Class S shares equal to 0.85% per annum of the aggregate NAV of its outstanding Class S shares; • with respect to the Company’s outstanding Class D shares equal to 0.3% per annum of the aggregate NAV of its outstanding Class D shares; and • with respect to the Company’s outstanding Class M shares equal to 0.3% per annum of the aggregate NAV of its outstanding Class M shares. The Company does not pay a stockholder servicing fee with respect to its Class I, Class F or Class Y shares. The dealer manager reallows some or all of the stockholder servicing fees to participating broker-dealers, servicing broker-dealers and financial institutions (including bank trust departments) for ongoing stockholder services performed by such broker-dealers, and waives (pays back to the Company) stockholder servicing fees to the extent a broker-dealer or financial institution is not eligible or otherwise declines to receive all or a portion of such fees. The Company will cease paying stockholder servicing fees with respect to any Class D, Class M, Class S and Class T shares held in a stockholder’s account at the end of the month in which the total underwriting compensation from the upfront selling commissions, dealer manager fees and stockholder servicing fees, as applicable, paid with respect to such account would exceed 1.25%, 7.25%, 8.75% and 8.75%, respectively (or a lower limit for shares sold by certain participating broker-dealers or financial institutions) of the gross proceeds from the sale of shares in such account. These amounts are referred to as the sales charge cap. At the end of such month that the sales charge cap is reached, each Class D, Class M, Class S or Class T share in such account will convert into a number of Class I shares (including any fractional shares) with an equivalent aggregate NAV as such share. In addition, the Company will cease paying stockholder servicing fees on each Class D share, Class M share, Class S share and Class T share held in a stockholder’s account and each such share will convert to Class I shares on the earlier to occur of the following: (i) a listing of Class I shares on a national securities exchange; (ii) the sale or other disposition of all or substantially all of the Company’s assets or the Company’s merger or consolidation with or into another entity in a transaction in which holders of Class D, Class M, Class S or Class T shares receive cash and/or shares of stock that are listed on a national securities exchange; or (iii) the date following the completion of the Company’s public offering on which, in the aggregate, underwriting compensation from all sources in connection with the Company’s public offering, including selling commissions, dealer manager fees, stockholder servicing fees and other underwriting compensation, is equal to 10% of the gross proceeds from its primary offering. The Company accrues future stockholder servicing fees in an amount equal to its best estimate of fees payable to FS Investment Solutions at the time such shares are sold. As of September 30, 2021 and December 31, 2020, the Company accrued $36,122 and $15,481, respectively, of stockholder servicing fees payable to FS Investment Solutions. FS Investment Solutions has entered into agreements with selected dealers distributing the Company’s shares in the public offering, which provide, among other things, for the re-allowance FS Investment Solutions also serves or served as the placement agent for the Company’s private offerings of Class F and Class Y shares pursuant to placement agreements. FS Investment Solutions does not receive any compensation pursuant to these agreements. Expense Limitation The Company has entered into an amended and restated expense limitation agreement with FS Real Estate Advisor and Rialto, or the expense limitation agreement, pursuant to which FS Real Estate Advisor and Rialto have agreed to waive reimbursement of or pay, on a quarterly basis, the Company’s annualized ordinary operating expenses for such quarter to the extent such expenses exceed 1.5% per annum of its average net assets attributable to each of its classes of common stock. The Company will repay FS Real Estate Advisor or Rialto on a quarterly basis any ordinary operating expenses previously waived or paid, but only if the reimbursement would not cause the then-current expense limitation, if any, to be exceeded. In addition, the reimbursement of expenses will be made only if payable not more than three years from the end of the fiscal quarter in which the expenses were paid or waived. FS Real Estate Advisor and Rialto each agreed to waive the recoupment of any amounts that may be subject to conditional reimbursement during the quarterly period ended March 31, 2020. To the extent that the conditions to recoupment are satisfied in a future quarter (prior to the expiration of the three-year period for reimbursement set forth in the expense limitation agreement), such expenses may be subject to conditional recoupment in accordance with the terms of the expense limitation agreement. During the period from September 13, 2017 (Commencement of Operations) to September 30, 2021, the Company accrued $5,839 for reimbursement of expenses that FS Real Estate Advisor and Rialto paid or waived, including $56 in reimbursements for the nine months ended September 30, 2021. During the period from September 13, 2017 (Commencement of Operations) to September 30, 2021, the Company received $5,839 in cash reimbursements from FS Real Estate Advisor. As of September 30, 2021 and December 31, 2020 $0 and $444, respectively, of During the nine months ended September 30, 2021, $390 of expense recoupments were paid to FS Real Estate Advisor and Rialto. As of September 30, 2021 and December 31, 2020, $8 and $0, respectively, The following table reflects the amounts paid or waived by FS Real Estate Advisor and Rialto under the expense limitation agreement and the expiration date for future possible reimbursements by the Company: For the Three Months Ended Amount of Recoupable Recoupment Expired Recoupment eligibility expiration September 30, 2021 $ — $ — $ — $ — N/A June 30, 2021 — — — — N/A March 31, 2021 56 56 — — March 31, 2023 December 31, 2020 444 444 — — December 31, 2023 September 30, 2020 397 397 — — September 30, 2023 June 30, 2020 182 182 — — June 30, 2023 March 31, 2020 — — — — N/A December 31, 2019 500 500 — — December 31, 2022 September 30, 2019 491 491 — — September 30, 2022 June 30, 2019 420 420 — — June 30, 2022 March 31, 2019 537 537 — — March 31, 2022 December 31, 2018 709 709 — — December 31, 2021 September 30, 2018 645 — 8 637 Expired September 30, 2021 June 30, 2018 561 — 390 171 Expired June 30, 2021 March 31, 2018 356 — — 356 Expired March 31, 2021 December 31, 2017 377 — — 377 Expired December 31, 2020 September 30, 2017 164 — — 164 Expired September 30, 2020 $ 5,839 $ 3,736 $ 398 $ 1,705 Capital Contributions and Commitments In December 2016, pursuant to a private placement, Michael C. Forman and David J. Adelman, principals of FS Investments, contributed an aggregate of $200 to purchase 8,000 Class F shares at the price of $25.00 per share. These individuals will not tender these shares of common stock for repurchase as long as FS Real Estate Advisor remains the Company’s adviser. FS Investments is controlled by Mr. Forman, the Company’s president and chief executive officer, and Mr. Adelman. Each of FS Investments and Rannel Investments, LLC (f/k/a Rialto Investments, LLC) (“RI”), a former affiliate of Rialto, the sub-adviser, Following the sale of Rialto in November 2018, RI remained a wholly-owned subsidiary of Lennar Corporation and no longer has any affiliation with Rialto or the Company other than its ownership of the Company’s Class F shares. On October 25, 2019, the Company’s board of directors approved the termination of RI’s remaining commitment to purchase Class F shares and agreed that the Company may repurchase up to approximately $17,000 of RI’s Class F shares, in its discretion and in one or more repurchases, outside the Company’s share repurchase plan at the most recently published NAV per Class F share at the time of any such repurchase. As of December 31, 2020, all of these shares were repurchased by the Company outside of the share repurchase plan at an average price of $24.95 per Class F share. On February 14, 2020, the Company repurchased, outside of the share repurchase plan, approximately $14,700 of its Class F shares from MCFDA SCV LLC, a special purpose vehicle jointly owned by Michael C. Forman and David J. Adelman, the principals of FS Investments, at the then-current transaction price of $24.95 per share. As of November 8,

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stockholders' Equity	Note 7. Stockholders’ Equity Below is a summary of transactions with respect to shares of the Company’s common Shares Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2020 912,469 137,116 1,245,658 5,778,640 546,298 1,971,039 2,171,528 12,762,748 Issuance of common stock 0 843,659 96,414 10,303,946 129,097 953,885 6,081,562 18,408,563 Reinvestment of distributions 23,310 0 29,916 214,826 9,827 36,910 67,801 382,590 Redemptions of common stock (33,638 ) (74,127 ) (27,614 ) (86,170 ) (14,551 ) (71,799 ) (67,142 ) (375,041 ) Transfers in or out (6,392 ) 0 (3,664 ) (1,684 ) (50,714 ) (85,401 ) 151,380 3,525 Balance as of September 30, 2021 895,749 906,648 1,340,710 16,209,558 619,957 2,804,634 8,405,129 31,182,385 Amount Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2020 $ 22,378 $ 3,449 $ 29,971 $ 134,705 $ 13,573 $ 46,154 $ 53,597 $ 303,827 Issuance of common stock 0 20,749 2,419 260,437 3,242 23,996 149,202 460,045 Reinvestment of distributions 585 0 750 5,429 247 929 1,663 9,603 Redemptions of common stock (843 ) (1,827 ) (692 ) (2,177 ) (365 ) (1,804 ) (1,646 ) (9,354 ) Transfers in or out (160 ) 0 (92 ) (43 ) (1,274 ) (2,145 ) 3,714 0 Accrued stockholder servicing fees (1) 0 0 (87 ) (20,817 ) (27 ) (1,468 ) 0 (22,399 ) Balance as of September 30, 2021 $ 21,960 $ 22,371 $ 32,269 $ 377,534 $ 15,396 $ 65,662 $ 206,530 $ 741,722 Shares Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2019 1,475,155 141,116 981,836 1,351,587 322,602 1,357,818 1,230,360 6,860,474 Issuance of common stock — — 248,615 3,342,412 240,665 642,576 978,832 5,453,100 Reinvestment of distributions 21,354 — 25,610 46,607 7,472 24,494 22,264 147,801 Redemptions of common stock (591,722 ) — (42,441 ) (284,499 ) (10,304 ) (205,668 ) (396,702 ) (1,531,336 ) Transfers in or out — — — — — (14,283 ) 14,621 338 Balance as of September 30, 2020 904,787 141,116 1,213,620 4,456,107 560,435 1,804,937 1,849,375 10,930,377 Amount Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2019 $ 36,419 $ 3,548 $ 23,616 $ 31,429 $ 8,015 $ 31,757 $ 30,367 $ 165,151 Issuance of common stock — — 6,253 84,726 6,054 16,202 24,113 137,348 Reinvestment of distributions 532 — 643 1,178 188 617 548 3,706 Redemptions of common stock (14,766 ) — (1,067 ) (7,184 ) (259 ) (5,175 ) (9,733 ) (38,184 ) Transfers in or out — — — — — (361 ) 361 — Accrued stockholder servicing fees (1) — — (257 ) (6,351 ) (73 ) (790 ) — (7,471 ) Balance as of September 30, 2020 $ 22,185 $ 3,548 $ 29,188 $ 103,798 $ 13,925 $ 42,250 $ 45,656 $ 260,550 (1) Stockholder servicing fees only apply to Class T, Class S, Class D and Class M shares. Under GAAP, the Company accrues future stockholder servicing fees in an amount equal to its best estimate of fees payable to FS Investment Solutions at the time such shares are sold. For purposes of NAV, the Company recognizes the stockholder servicing fee as a reduction of NAV on a monthly basis. As a result, the estimated liability for the future stockholder servicing fees, which are accrued at the time each share is sold, will have no effect on the NAV of any class. Share Repurchase Plan The Company has adopted an amended and restated share repurchase plan, or share repurchase plan, whereby on a monthly basis, stockholders may request that the Company repurchase all or any portion of their shares. The repurchase of shares is limited to no more than 2% of the Company’s aggregate NAV per month of all classes of shares then participating in the share repurchase plan and no more than 5% of the Company’s aggregate NAV per calendar quarter of all classes of shares then participating in the share repurchase plan, which means that in any 12-month During the three months ended September 30, 2021 and 2020, the Company repurchased 165,004 and 132,745, respectively, shares of common stock under its share repurchase plan representing a total of $4,121 and $3,338, respectively. COVID-19 Distribution Reinvestment Plan Pursuant to the Company’s distribution reinvestment plan, holders of shares of any class of the Company’s common stock may elect to have their cash distributions reinvested in additional shares of the Company’s common stock. The purchase price for shares pursuant to the distribution reinvestment plan will be equal to the transaction price for such shares at the time the distribution is payable. Distributions The Company generally intends to distribute substantially all of its taxable income, which does not necessarily equal net income as calculated in accordance with GAAP, to its stockholders each year to comply with the REIT provisions of the Code. Dividends are paid first to the holders of the Company’s Series A preferred stock at the rate of 12.0% per annum plus all accumulated and unpaid dividends thereon, and then to the holders of the Company’s common stock. All distributions will be made at the discretion of the Company’s board of directors and will depend upon its taxable income, financial condition, maintenance of REIT status, applicable law, and other factors that the Company’s board of directors deems relevant. The following table reflects the cash distributions per share that the Company paid on its common stock during the nine months ended September 30, 2021: Record Date Class F Class Y Class T Class S Class D Class M Class I January 28, 2021 $ 0.1710 $ 0.1710 $ 0.1273 $ 0.1273 $ 0.1388 $ 0.1388 $ 0.1450 February 25, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 March 30, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 April 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 May 27, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 June 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 July 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 August 30, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 September 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 Total $ 1.5390 $ 1.5390 $ 1.1457 $ 1.1457 $ 1.2492 $ 1.2492 $ 1.3050 The following table reflects the amount of cash distributions that the Company paid on its common stock during the three and nine months ended September 30, 2021, and 2020: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Distributions: Paid or payable in cash $ 6,505 $ 2,912 $ 14,861 $ 7,993 Reinvested in shares 4,448 1,365 9,603 3,706 Total distributions $ 10,953 $ 4,277 $ 24,464 $ 11,699 Source of distributions: Cash flows from operating activities $ 10,953 (1) $ 4,277 $ 24,464 $ 11,699 Offering proceeds — — — — Total sources of distributions $ 10,953 $ 4,277 $ 24,464 $ 11,699 Net cash provided by operating activities ( 2 $ 10,275 4,904 $ 27,591 $ 18,993 (1) The distributions for the three months ended September 30, 2021, were fully covered by cash flows from operating activities, including cash flows from prior periods of $678. ( 2 Cash flows from operating activities are supported by expense support payments from FS Real Estate Advisor and Rialto pursuant to the Company’s expense limitation agreement. See Note 6 for additional information regarding the Company’s expense limitation agreement. The Company currently declares and pays regular cash distributions on a monthly basis. The Company’s board of directors previously authorized regular monthly cash distributions for October 2021 and November 2021 Class F Class Y Class T Class S Class D Class M Class I $0.1610 $0.1610 $0.1173 $0.1173 $0.1288 $0.1288 $0.1350 The distributions for each class of outstanding common stock have been or will be paid monthly to stockholders of record as of the monthly record dates previously determined by the Company’s board of directors. These distributions have been or will be paid in cash or reinvested in shares of the Company’s common stock for stockholders participating in the Company’s distribution reinvestment plan.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Note 8. Fair Value of Financial Instruments The following table presents the Company’s financial instruments carried at fair value in the consolidated balance sheets by its level in the fair value hierarchy: September 30, 2021 (Unaudited) December 31, 2020 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Mortgage-backed securities available-for-sale $ 48,737 — $ 48,737 — — — — — As discussed in Note 2, GAAP requires disclosure of fair value information about financial instruments, whether or not recognized in the statement of financial position, for which it is practicable to estimate that value. The following table details the carrying amount, face amount, and fair value of the financial instruments described in Note 2: September 30, 2021 (Unaudited) December 31, 2020 Book Value Face Fair Value Book Face Fair Value Financial Assets Cash, cash equivalents and restricted cash $ 105,314 $ 105,314 $ 105,314 $ 17,874 $ 17,874 $ 17,874 Loans receivable - held-for-investment (1) $ 2,511,901 $ 2,511,999 $ 2,515,244 $ 700,149 $ 699,250 $ 697,533 Mortgage-backed securities held-to-maturity $ 37,723 $ 50,300 $ 37,723 $ 37,314 $ 50,300 $ 37,314 Financial Liabilities Repurchase obligations (2) $ 906,010 $ 908,083 $ 908,083 $ 125,266 $ 125,460 $ 125,460 Credit facility $ 40,000 $ 40,000 $ 40,000 — — — Collateralized loan obligations (2) $ 964,434 $ 974,600 $ 974,600 $ 323,109 $ 327,665 $ 327,665 (1) Book value of loans receivable represents the face amount, net of unamortized loan fees and costs and accrual of exit fees, as applicable. (2) Book value represents the face amount, net of deferred financing costs. held-to-maturity,

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Note 9. Variable Interest Entities Consolidated Variable Interest Entities The Company has financed a portion of its loans through CLOs, which are considered VIEs. The Company has a controlling financial interest in the CLOs and, therefore, consolidates them on its balance sheet because the Company has both (i) the power to direct activities of the CLOs that most significantly affect the CLOs’ economic performance and (ii) the obligation to absorb losses and the right to receive benefits of the CLOs that could potentially be significant to the CLOs. The following table details the assets and liabilities of the Company’s consolidated CLOs as of September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Assets: Restricted cash $ 3,938 $ 4 Loans receivable, held-for-investment 1,204,940 411,455 Interest receivable 3,486 2,470 Other assets — 15,842 Total assets $ 1,212,364 $ 429,771 Liabilities Collateralized loan obligations (net of deferred financing $ 964,434 $ 323,109 Interest payable 638 227 Other liabilities 205 — Total liabilities $ 965,277 $ 323,336 Assets held by the VIEs are restricted and can be used only to settle obligations of the VIEs. The liabilities are non-recourse Non-Consolidated In August 2020, the Company invested $37,005 in a subordinated position of a CMBS trust which is considered a VIE. The Company is not the primary beneficiary of the VIE because it does not have the power to direct the activities that most significantly affect the VIE’s economic performance, nor does it provide guarantees or recourse to the VIE other than standard representations and warranties and, therefore, does not consolidate the VIE on its balance sheet. The Company has classified its investment in the CMBS as a held-to-maturity The Company is not obligated to provide, nor has it provided financial support to these consolidated and non-consolidated

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 10. Commitments and Contingencies The Company enters into contracts that contain a variety of indemnification provisions. The Company’s maximum exposure under these arrangements is unknown; however, the Company has not had prior claims or losses pursuant to these contracts. Management of FS Real Estate Advisor has reviewed the Company’s existing contracts and expects the risk of loss to the Company to be remote. The Company is not currently subject to any material legal proceedings and, to the Company’s knowledge, no material legal proceedings are threatened against the Company. From time to time, the Company may be party to certain legal proceedings in the ordinary course of business. While the outcome of any legal proceedings cannot be predicted with certainty, the Company does not expect that any such proceedings will have a material effect on its financial condition or results of operations. See Note 6 for a discussion of the Company’s commitments to FS Real Estate Advisor and its affiliates (including FS Investments) for the reimbursement of organization and offering costs funded by FS Investments and for the reimbursement of amounts paid or waived by FS Real Estate Advisor and Rialto under the expense limitation agreement.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Note 11. Subsequent Events The following is a discussion of material events that have occurred subsequent to September 30, 2021 through the issuance of the unaudited consolidated financial statements. Status of Offerings As of November 8, 2021, the Company has issued 40,255,586 shares of common stock (consisting of 2,613,583 shares of Class F common stock, 1,036,671 shares of Class Y common stock, 1,463,744 shares of Class T common stock, 20,280,778 shares of Class S common stock, 736,287 shares of Class D common stock, 3,434,785 shares of Class M common stock and 10,689,738 shares of Class I common stock), including shares issued pursuant to its distribution reinvestment plan, for gross proceeds of $730,738. Share Repurchases In connection with the Company’s October 2021 repurchase period, the Company repurchased an aggregate of 238,300 shares of common stock representing a total of $5,853. Business Update During the period from October 1, 2021 through November 8, 2021, the Company closed on seven senior floating-rate mortgage loans and one fixed-rate mezzanine loan of which $368,755 and $66,633 was funded at closing, respectively. The Company funded the origination of the senior and mezzanine loans with cash on hand, proceeds from its public offerings and $81,869 in proceeds from the Company’s financing facilities. 2021-FL3 On November 4, 2021, the Company issued $928,483 of collateralized loan obligation notes, or the CLO3 Transaction, through the Sub-REIT and two wholly-owned financing subsidiaries of the Sub-REIT, FS Rialto 2021-FL3 Issuer, Ltd., an exempted company with limited liability under the laws of the Cayman Islands, as issuer, or the CLO3 Issuer, and FS Rialto 2021-FL3 Co-Issuer, LLC, a Delaware limited liability company, as co-issuer, or the CLO3 Co-Issuer and, together with the Issuer, the CLO3 Issuers. The CLO3 Issuers issued six classes of notes, or the CLO3 Offered Notes, (i) $657,736 Class A Senior Secured Floating Rate Notes Due 2036, which bear interest at LIBOR plus 1.25% per annum plus, on and after the September 2026 payment date, an additional 0.25% per annum, (ii) $42,526 Class A-S Second Priority Secured Floating Rate Notes Due 2036, which bear interest at LIBOR plus 1.55% per annum plus, on and after the September 2026 payment date, 0.25% per annum, (iii) $55,283 Class B Third Priority Secured Floating Rate Notes Due 2036, which bear interest at LIBOR plus 1.80% per annum plus, on and after the September 2026 payment date, 0.50% per annum, (iv) $69,459 Class C Fourth Priority Secured Floating Rate Notes Due 2036, which bear interest at LIBOR plus 2.05% per annum plus, on and after the September 2026 payment date, 0.50% per annum, (v) $80,799 Class D Fifth Priority Secured Floating Rate Notes Due 2036, or the Class D Notes, which bear interest at LIBOR plus 2.50% per annum plus, on and after the October 2026 payment date, 0.50% per annum, and (vi) $22,680 Class E Sixth Priority Secured Floating Rate Notes Due 2036, or the Class E Notes, which bear interest at LIBOR plus 2.85% per annum plus, on and after the October 2026 payment date, 0.50% per annum. In addition, the CLO3 Issuer further issued two classes of notes, or together with the CLO3 Offered Notes, the 2021-FL3 Notes, (i) $66,624 Class F Seventh Priority Floating Rate Notes Due 2036, or the Class F Notes, which bear interest at LIBOR plus 4.500% per annum, and (ii) $39,690 Class G Eighth Priority Floating Rate Notes Due 2036, or the Class G Notes, which bear interest at LIBOR plus 6.75% per annum. In addition, concurrently with the issuance of the 2021-FL3 Notes, the CLO3 Issuer issued 99,231 Preferred Shares, par value $0.001 per share, and with a liquidation preference equal to $1,000 per share, or the CLO3 Preferred Shares. The 2021-FL3 Notes will mature at par on the November 2036 payment date, unless redeemed or repaid prior thereto. The Company serves as the collateral manager for the CLO3 Issuer. The CLO3 Issuers issued or co-issued the 2021-FL3 Notes, as applicable, pursuant to the terms of an Indenture, dated as of November 4, 2021, or the CLO3 Indenture, by and among the CLO3 Issuers, the Company, as advancing agent, Wilmington Trust, National Association, as trustee, and Wells Fargo, as note administrator and custodian. FS Rialto 2021-FL3 Holder, LLC, which is an indirect wholly-owned subsidiary of the Company and a direct wholly-owned subsidiary of the Sub-REIT, acquired 100% of the Class F Notes, the Class G Notes and the Preferred Shares upon issuance. The CLO3 Offered Notes are limited recourse obligations of the CLO3 Issuer and non-recourse obligations of the CLO3 Co-Issuer payable solely from collateral interests acquired by the CLO3 Issuer and pledged under the CLO3 Indenture. To the extent the collateral is insufficient to make payments in respect of the CLO3 Offered Notes, none of the CLO3 Issuer, the CLO3 Co-Issuer, any of their respective affiliates nor any other person will have any obligation to pay any further amounts in respect of the CLO3 Offered Notes. The Class F Notes and the Class G Notes are not secured.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation: eliminated nature necessary statement
Use of Estimates	Use of Estimates:
Principles of Consolidation	Principles of Consolidation: The Company consolidates VIEs in which it is considered to be the primary beneficiary. The primary beneficiary is defined as the entity having both of the following characteristics: (1) the power to direct the activities that, when taken together, most significantly impact the VIE’s performance; and (2) the obligation to absorb losses and right to receive the returns from the VIE that would be significant to the VIE. The Company determines whether it is the primary beneficiary of an entity subject to consolidation based on a qualitative assessment of the VIE’s capital structure, contractual terms, nature of the VIE’s operations and purpose and the Company’s relative exposure to the related risks of the VIE on the date it becomes initially involved in the VIE. The Company reassesses its VIE determination with respect to an entity on an ongoing basis.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash: The following table provides a reconciliation of cash, cash equivalents and restricted cash in the Company’s consolidated balance sheets to the total amount shown in the Company’s unaudited consolidated statements of cash flows: September 30, 2021 2020 Cash and cash equivalents $ 99,839 $ 57,840 Restricted cash 5,475 2,316 Total cash, cash equivalents and restricted cash $ 105,314 $ 60,156
Loans Receivable and Provision for Loan Losses	Loans Receivable and Provision for Loan Losses: Loans that the Company originates or purchases that the Company is unable to hold, or intends to sell or otherwise dispose of, in the foreseeable future are classified as held-for-sale FS Real Estate Advisor and Rialto perform a quarterly review of the Company’s portfolio of loans. In connection with this review, FS Real Estate Advisor and Rialto assess the risk factors of each loan and assign a risk rating based on a variety of factors, including, without limitation, loan-to-value 5-point Loan Risk Rating Summary Description 1 Very Low Risk 2 Low Risk 3 Medium Risk 4 High Risk/Potential for Loss: A loan that has a risk of realizing a principal loss 5 Impaired/Loss Likely: A loan that has a very high risk of realizing a principal loss or has otherwise incurred a principal loss
Mortgage backed securities	Mortgage-backed Securities: held-to-maturity available-for-sale held-to-maturity Held-to-maturity available-for The Company regularly monitors its mortgage-backed securities to ensure investments that may be other-than-temporarily impaired are timely identified, properly valued and charged against earnings in the proper period. The determination that a security has incurred an other-than-temporary decline in value requires the judgment of management. Assessment factors include, but are not limited to, the length of time and the extent to which the market value has been less than amortized cost, the financial condition and rating of the issuer, and the intent to sell or whether it is more likely than not that the Company will be required to sell.
Fair Value of Financial Instruments	Fair Value of Financial Instruments: Fair Value Measurements and Disclosures ASC Topic 820 also establishes a fair value hierarchy that prioritizes and ranks the level of market price observability used in measuring financial instruments. Market price observability is affected by a number of factors, including the type of financial instrument, the characteristics specific to the financial instrument, and the state of the marketplace, including the existence and transparency of transactions between market participants. Financial instruments with readily available quoted prices in active markets generally will have a higher degree of market price observability and a lesser degree of judgment used in measuring fair value. Financial instruments measured and reported at fair value are classified and disclosed based on the observability of inputs used in the determination, as follows: Level 1: Generally includes only unadjusted quoted prices that are available in active markets for identical financial instruments as of the reporting date. Level 2: Pricing inputs include quoted prices in active markets for similar instruments, quoted prices in less active or inactive markets for identical or similar instruments where multiple price quotes can be obtained, and other observable inputs, such as interest rates, yield curves, credit risks, and default rates. Level 3: Pricing inputs are unobservable for the financial instruments and include situations where there is little, if any, market activity for the financial instrument. These inputs require significant judgment or estimation by management or third parties when determining fair value and generally represent anything that does not meet the criteria of Levels 1 and 2. The estimated value of each asset reported at fair value using Level 3 inputs is determined by an internal committee composed of members of senior management of FS Real Estate Advisor. Certain of the Company’s assets are reported at fair value either (i) on a recurring basis, as of each quarter-end, The Company is also required by GAAP to disclose fair value information about financial instruments that are not otherwise reported at fair value in the Company’s consolidated balance sheets, to the extent it is practicable to estimate a fair value for those instruments. These disclosure requirements exclude certain financial instruments and all non-financial The following methods and assumptions are used to estimate the fair value of each class of financial instruments, for which it is practicable to estimate that value: • Cash and cash equivalents: The carrying amount of cash on deposit and in money market funds approximates fair value. • Restricted cash: The carrying amount of restricted cash approximates fair value. • Loans receivable, net: The fair values for these loans were estimated by FS Real Estate Advisor based on discounted cash flow methodology taking into consideration factors, including capitalization rates, discount rates, leasing, occupancy rates, availability and cost of financing, exit plan, sponsorship, actions of other lenders, and indications of market value from other market participants. • Mortgage-backed securities available-for-sale: • Mortgage-backed securities held-to-maturity: • Collateralized loan obligations, repurchase obligations and credit facility: The fair values for these instruments were estimated based on the rate at which similar credit facilities would have currently been priced.
Deferred Financing Costs	Deferred Financing Costs: costs
Revenue Recognition	Revenue Recognition: ex-dividend Loans are considered past due when payments are not made in accordance with the contractual terms. The Company does not accrue as receivable interest on loans if it is not probable that such income will be collected. Loans are placed on non-accrual non-accrual non-performing
Organization Costs	Organization Costs: other
Offering Costs	Offering Costs: paid-in
Income Taxes	Income Taxes:
Uncertainty in Income Taxes	Uncertainty in Income Taxes expense
Stockholder Servicing Fees	Stockholder Servicing Fees: follows Liabilities paid-in
Recent Accounting Pronouncements	Recent Accounting Pronouncements: 2016-13, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments (Topic 326) 2016-13. 2016-13 2016-13 available-for-sale 2019-10, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instrument (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) Effective Dates, 2016-13

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Reconciliation of Cash, Cash Equivalents and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents and restricted cash in the Company’s consolidated balance sheets to the total amount shown in the Company’s unaudited consolidated statements of cash flows: September 30, 2021 2020 Cash and cash equivalents $ 99,839 $ 57,840 Restricted cash 5,475 2,316 Total cash, cash equivalents and restricted cash $ 105,314 $ 60,156

Loans Receivable (Tables)

Loans Receivable (Tables)	9 Months Ended
	Sep. 30, 2021
Receivables [Abstract]
Summary of Details Overall Statistics for Loans Receivable Portfolio	The following table details overall statistics for the Company’s loans receivable portfolio as of September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Number of loans 78 35 Principal balance $ 2,511,999 $ 699,250 Net book value $ 2,511,901 $ 700,149 Unfunded loan commitments (1) $ 185,674 $ 100,389 Weighted-average cash coupon (2) L+3.54 % L+4.25 % Weighted-average all-in (2) L+3.58 % L+4.35 % Weighted-average maximum maturity (years) (3) 4.4 3.7 (1) The Company may be required to provide funding when requested by the borrower in accordance with the terms of the underlying agreements. (2) The Company’s floating-rate loans are indexed to the London Interbank Offered Rate, or LIBOR. In addition to cash coupon, all-in (3) Maximum maturity assumes all extension options are exercised by the borrower; however, loans may be repaid prior to such date.
Summary of Activity in Loan Portfolio	For the nine months ended September 30, 2021 and 2020, the activity in the Company’s loan portfolio, was as follows: For the Nine Months Ended September 30, 2021 2020 Balance at beginning of period $ 700,149 $ 406,645 Loan fundings 1,990,205 214,855 Loan repayments (178,428 ) (22,988 ) Amortization of deferred fees on loans 702 680 Exit and extension fees received on loans (727 ) (167 ) Balance at end of period $ 2,511,901 $ 599,015
Schedule of Loan Receivables Acquired By Property	The following tables detail the property type and geographic location of the properties securing the loans in the Company’s loans receivable, held-for-investment September 30, 2021 (Unaudited) December 31, 2020 Property Type Net Book Value Percentage Net Book Value Percentage Office $ 292,375 12 % $ 174,483 25 % Industrial 305,172 12 % 168,876 24 % Multifamily 1,518,516 60 % 130,648 19 % Mixed Use 112,578 4 % 91,556 13 % Hospitality 63,422 3 % 62,759 9 % Retail 55,283 2 % 52,128 7 % Self Storage 164,555 7 % 19,699 3 % Total $ 2,511,901 100 % $ 700,149 100 %
Schedule of Loan Receivables Acquired By Geographics	September 30, 2021 (Unaudited) December 31, 2020 Geographic Location (1) Net Book Value Percentage Net Book Value Percentage South $ 1,400,387 56 % $ 311,123 44 % West 475,730 19 % 201,318 29 % Northeast 394,132 15 % 168,009 24 % Midwest 221,952 9 % — — Various 19,700 1 % 19,699 3 % Total $ 2,511,901 100 % $ 700,149 100 % (1) As defined by the United States Department of Commerce, Bureau of the Census.
Loans receivable based on internal risk ratings	The following table allocates the net book value of the Company’s loans receivable, held-for-investment September 30, 2021 (Unaudited) December 31, 2020 Risk Rating Number of Net Book Percentage Number of Net Book Percentage 1 — $ — — — $ — — 2 — — — — — — 3 78 2,511,901 100 % 34 689,104 98 % 4 — — — 1 11,045 2 % 5 — — — — — — Total 78 $ 2,511,901 100 % 35 $ 700,149 100 %

Mortgage Backed Securities (Tab

Mortgage Backed Securities (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Available-for-sale Securities Reconciliation	The table below summarizes various attributes of the Company’s investments in available-for-sale Gross Unrealized Weighted Average Outstanding Face Amortized Gains Losses Fair Coupon Remaining September 30, 2021 (Unaudited) CMBS, available-for-sale $ 48,664 $ 48,633 $ 137 $ (33 ) $ 48,737 6.47 % 16.2 December 31, 2020 CMBS, available-for-sale $ — $ — $ — $ — $ — — % —
Summary of Investment Held-to-maturity CMBS	The table below summarizes various attributes of the Company’s investments in held-to-maturity Net Carrying Gross Gross Fair Value September 30, 2021 (Unaudited) CMBS, held-to-maturity $ 37,723 — — $ 37,723 December 31, 2020 CMBS, held-to-maturity $ 37,314 — — $ 37,314
Summary of Maturities of Investment Held-to-maturity CMBS	The table below summarizes the maturities of the Company’s investments in held-to-maturity Total Less than 1 year 1-3 years 3-5 years More than 5 years CMBS, held-to-maturity $ 37,723 — — $ 37,723 —

Financing Arrangements (Tables)

Financing Arrangements (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Summary of Information of Outstanding Financing Arrangement	The following tables present summary information with respect to the Company’s outstanding financing arrangements as of September 30, 2021 and December 31, 2020. For additional information regarding these financing arrangements, see the notes to the Company’s audited consolidated financial statements contained in its annual report on Form 10-K As of September 30, 2021 (Unaudited) Arrangement (1) Rate Amount Amount Maturity Date Carrying Fair Value Collateralized Loan Obligations 2019-FL1 L+1.20% — 2.50% (2) $ 327,665 $ — December 18, 2036 (3) $ 422,345 $ 423,079 2021-FL2 L+1.22% — 3.45% (2) 646,935 — May 5, 2038 (4) 782,595 784,983 974,600 — 1,204,940 1,208,062 Repurchase Agreements WF-1 L+2.15% — 2.50% (5) 314,092 35,908 August 30, 2022 392,642 392,816 GS-1 L+1.75% — 2.75% (6) 151,257 23,743 January 26, 2022 190,981 191,025 BB-1 L+1.55% — 1.95% 416,803 33,197 February 22, 2024 520,745 521,125 RBC Facility L+1.35% 25,931 — N/A 36,580 36,683 908,083 92,848 1,140,948 1,141,649 Revolving Credit Facility CNB Facility L+2.25% (7) 40,000 15,000 June 7, 2023 — — MM-1 L+2.10% (2) — 200,000 September 20, 2029 — — 40,000 215,000 — — Total $ 1,922,683 $ 307,848 $ 2,345,888 $ 2,349,711 As of December 31, 2020 Arrangement (1) Rate Amount Amount Maturity Date Carrying Fair Value Collateralized Loan Obligation 2019-FL1 L+1.20% — 2.50% (2) $ 327,665 $ — December 18, 2036 (3) $ 411,455 $ 409,497 Repurchase Agreements WF-1 L+2.15% — 2.50% (5) 29,889 70,111 August 30, 2021 39,945 39,977 GS-1 L+1.75% — 2.75% (6) 95,571 79,429 January 26, 2021 127,512 126,995 125,460 149,540 167,457 166,972 Revolving Credit Facility CNB Facility L+2.25% (2) — 25,000 August 23, 2022 — — Total $ 453,125 $ 174,540 $ 578,912 $ 576,469 (1) The carrying amount outstanding under the facilities approximates their fair value. (2) LIBOR is subject to a 0.00% floor. (3) The 2019-FL1 2019-FL1 (4) The 2021-FL2 2021-FL2 (5) LIBOR is subject to a 0.00% floor. WF-1 (6) LIBOR is subject to a 0.50% floor. GS-1 and (7) LIBOR is subject to a 0.50% floor.

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Schedule of Related Party Transactions [Table Text Block]	The following table describes the fees and expenses accrued under the advisory agreement during the three and nine months ended September 30, 2021 and 2020: Three Months Ended Nine Months Ended Related Party Source Agreement Description 2021 2020 2021 2020 FS Real Estate Advisor Advisory Agreement Base Management Fee (1) $ 1,944 $ 760 $ 4,269 $ 2,076 FS Real Estate Advisor Advisory Agreement Performance Fee (2) $ 8 $ 465 $ 968 903 FS Real Estate Advisor Advisory Agreement Administrative Services Expenses (3) $ 1,260 $ 810 $ 2,708 $ 1,698 (1) During the nine months ended September 30, 2021 and 2020, $3,194 and $1,642, respectively, in base management fees were paid to FS Real Estate Advisor. As of September 30, 2021 and December 31, 2020 and $869, respectively, (2) During the nine months ended September 30, 2021 and 2020, $1,276 and $438, respectively, in performance fees were paid to FS Real Estate Advisor. As of September 30, 2021 and December 31, 2020, $8 and $316, respectively, (3) During the nine months ended September 30, 2021 and 2020, $2,448 and $1,610, respectively, of the accrued administrative services expenses related to the allocation of costs of administrative personnel for services rendered to the Company by FS Real Estate Advisor and Rialto and the remainder related to other reimbursable expenses. These amounts are recorded as general and administrative expenses on the accompanying unaudited consolidated statements of operations.
Schedule Of Expense Reimbursed	The following table reflects the amounts paid or waived by FS Real Estate Advisor and Rialto under the expense limitation agreement and the expiration date for future possible reimbursements by the Company: For the Three Months Ended Amount of Recoupable Recoupment Expired Recoupment eligibility expiration September 30, 2021 $ — $ — $ — $ — N/A June 30, 2021 — — — — N/A March 31, 2021 56 56 — — March 31, 2023 December 31, 2020 444 444 — — December 31, 2023 September 30, 2020 397 397 — — September 30, 2023 June 30, 2020 182 182 — — June 30, 2023 March 31, 2020 — — — — N/A December 31, 2019 500 500 — — December 31, 2022 September 30, 2019 491 491 — — September 30, 2022 June 30, 2019 420 420 — — June 30, 2022 March 31, 2019 537 537 — — March 31, 2022 December 31, 2018 709 709 — — December 31, 2021 September 30, 2018 645 — 8 637 Expired September 30, 2021 June 30, 2018 561 — 390 171 Expired June 30, 2021 March 31, 2018 356 — — 356 Expired March 31, 2021 December 31, 2017 377 — — 377 Expired December 31, 2020 September 30, 2017 164 — — 164 Expired September 30, 2020 $ 5,839 $ 3,736 $ 398 $ 1,705

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Summary of Common Stock Transactions	Below is a summary of transactions with respect to shares of the Company’s common Shares Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2020 912,469 137,116 1,245,658 5,778,640 546,298 1,971,039 2,171,528 12,762,748 Issuance of common stock 0 843,659 96,414 10,303,946 129,097 953,885 6,081,562 18,408,563 Reinvestment of distributions 23,310 0 29,916 214,826 9,827 36,910 67,801 382,590 Redemptions of common stock (33,638 ) (74,127 ) (27,614 ) (86,170 ) (14,551 ) (71,799 ) (67,142 ) (375,041 ) Transfers in or out (6,392 ) 0 (3,664 ) (1,684 ) (50,714 ) (85,401 ) 151,380 3,525 Balance as of September 30, 2021 895,749 906,648 1,340,710 16,209,558 619,957 2,804,634 8,405,129 31,182,385 Amount Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2020 $ 22,378 $ 3,449 $ 29,971 $ 134,705 $ 13,573 $ 46,154 $ 53,597 $ 303,827 Issuance of common stock 0 20,749 2,419 260,437 3,242 23,996 149,202 460,045 Reinvestment of distributions 585 0 750 5,429 247 929 1,663 9,603 Redemptions of common stock (843 ) (1,827 ) (692 ) (2,177 ) (365 ) (1,804 ) (1,646 ) (9,354 ) Transfers in or out (160 ) 0 (92 ) (43 ) (1,274 ) (2,145 ) 3,714 0 Accrued stockholder servicing fees (1) 0 0 (87 ) (20,817 ) (27 ) (1,468 ) 0 (22,399 ) Balance as of September 30, 2021 $ 21,960 $ 22,371 $ 32,269 $ 377,534 $ 15,396 $ 65,662 $ 206,530 $ 741,722 Shares Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2019 1,475,155 141,116 981,836 1,351,587 322,602 1,357,818 1,230,360 6,860,474 Issuance of common stock — — 248,615 3,342,412 240,665 642,576 978,832 5,453,100 Reinvestment of distributions 21,354 — 25,610 46,607 7,472 24,494 22,264 147,801 Redemptions of common stock (591,722 ) — (42,441 ) (284,499 ) (10,304 ) (205,668 ) (396,702 ) (1,531,336 ) Transfers in or out — — — — — (14,283 ) 14,621 338 Balance as of September 30, 2020 904,787 141,116 1,213,620 4,456,107 560,435 1,804,937 1,849,375 10,930,377 Amount Class F Class Y Class T Class S Class D Class M Class I Total Balance as of December 31, 2019 $ 36,419 $ 3,548 $ 23,616 $ 31,429 $ 8,015 $ 31,757 $ 30,367 $ 165,151 Issuance of common stock — — 6,253 84,726 6,054 16,202 24,113 137,348 Reinvestment of distributions 532 — 643 1,178 188 617 548 3,706 Redemptions of common stock (14,766 ) — (1,067 ) (7,184 ) (259 ) (5,175 ) (9,733 ) (38,184 ) Transfers in or out — — — — — (361 ) 361 — Accrued stockholder servicing fees (1) — — (257 ) (6,351 ) (73 ) (790 ) — (7,471 ) Balance as of September 30, 2020 $ 22,185 $ 3,548 $ 29,188 $ 103,798 $ 13,925 $ 42,250 $ 45,656 $ 260,550 (1) Stockholder servicing fees only apply to Class T, Class S, Class D and Class M shares. Under GAAP, the Company accrues future stockholder servicing fees in an amount equal to its best estimate of fees payable to FS Investment Solutions at the time such shares are sold. For purposes of NAV, the Company recognizes the stockholder servicing fee as a reduction of NAV on a monthly basis. As a result, the estimated liability for the future stockholder servicing fees, which are accrued at the time each share is sold, will have no effect on the NAV of any class.
Summary of Cash Distributions Per Share that Paid on its Common Stock	The following table reflects the cash distributions per share that the Company paid on its common stock during the nine months ended September 30, 2021: Record Date Class F Class Y Class T Class S Class D Class M Class I January 28, 2021 $ 0.1710 $ 0.1710 $ 0.1273 $ 0.1273 $ 0.1388 $ 0.1388 $ 0.1450 February 25, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 March 30, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 April 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 May 27, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 June 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 July 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 August 30, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 September 29, 2021 0.1710 0.1710 0.1273 0.1273 0.1388 0.1388 0.1450 Total $ 1.5390 $ 1.5390 $ 1.1457 $ 1.1457 $ 1.2492 $ 1.2492 $ 1.3050 The following table reflects the amount of cash distributions that the Company paid on its common stock during the three and nine months ended September 30, 2021, and 2020: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Distributions: Paid or payable in cash $ 6,505 $ 2,912 $ 14,861 $ 7,993 Reinvested in shares 4,448 1,365 9,603 3,706 Total distributions $ 10,953 $ 4,277 $ 24,464 $ 11,699 Source of distributions: Cash flows from operating activities $ 10,953 (1) $ 4,277 $ 24,464 $ 11,699 Offering proceeds — — — — Total sources of distributions $ 10,953 $ 4,277 $ 24,464 $ 11,699 Net cash provided by operating activities ( 2 $ 10,275 4,904 $ 27,591 $ 18,993 (1) The distributions for the three months ended September 30, 2021, were fully covered by cash flows from operating activities, including cash flows from prior periods of $678. ( 2 Cash flows from operating activities are supported by expense support payments from FS Real Estate Advisor and Rialto pursuant to the Company’s expense limitation agreement. See Note 6 for additional information regarding the Company’s expense limitation agreement.
Schedule of Cash Distribution on Class of Common Stock	The Company currently declares and pays regular cash distributions on a monthly basis. The Company’s board of directors previously authorized regular monthly cash distributions for October 2021 and November 2021 Class F Class Y Class T Class S Class D Class M Class I $0.1610 $0.1610 $0.1173 $0.1173 $0.1288 $0.1288 $0.1350

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	The following table presents the Company’s financial instruments carried at fair value in the consolidated balance sheets by its level in the fair value hierarchy: September 30, 2021 (Unaudited) December 31, 2020 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Mortgage-backed securities available-for-sale $ 48,737 — $ 48,737 — — — — —
Summary of Carrying Amount, Face Amount, and Fair Value of Financial Instruments	The following table details the carrying amount, face amount, and fair value of the financial instruments described in Note 2: September 30, 2021 (Unaudited) December 31, 2020 Book Value Face Fair Value Book Face Fair Value Financial Assets Cash, cash equivalents and restricted cash $ 105,314 $ 105,314 $ 105,314 $ 17,874 $ 17,874 $ 17,874 Loans receivable - held-for-investment (1) $ 2,511,901 $ 2,511,999 $ 2,515,244 $ 700,149 $ 699,250 $ 697,533 Mortgage-backed securities held-to-maturity $ 37,723 $ 50,300 $ 37,723 $ 37,314 $ 50,300 $ 37,314 Financial Liabilities Repurchase obligations (2) $ 906,010 $ 908,083 $ 908,083 $ 125,266 $ 125,460 $ 125,460 Credit facility $ 40,000 $ 40,000 $ 40,000 — — — Collateralized loan obligations (2) $ 964,434 $ 974,600 $ 974,600 $ 323,109 $ 327,665 $ 327,665 (1) Book value of loans receivable represents the face amount, net of unamortized loan fees and costs and accrual of exit fees, as applicable. (2) Book value represents the face amount, net of deferred financing costs.

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of detailed information about the assets and liabilities	The following table details the assets and liabilities of the Company’s consolidated CLOs as of September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Assets: Restricted cash $ 3,938 $ 4 Loans receivable, held-for-investment 1,204,940 411,455 Interest receivable 3,486 2,470 Other assets — 15,842 Total assets $ 1,212,364 $ 429,771 Liabilities Collateralized loan obligations (net of deferred financing $ 964,434 $ 323,109 Interest payable 638 227 Other liabilities 205 — Total liabilities $ 965,277 $ 323,336

Principal Business and Organi_2

Principal Business and Organization - Additional Information (Detail) - Class T, Class S, Class D, Class M and Class I shares [Member] - Maximum [Member]	9 Months Ended
	Sep. 30, 2021USD ($)
Subsidiary, Sale of Stock [Line Items]
Common stock value submitted for approval under initial public offering	$ 2,750,000,000
Primary Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock value submitted for approval under initial public offering	2,500,000,000
Distribution Reinvestment Plan [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock value submitted for approval under initial public offering	$ 250,000,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 99,839	$ 15,707	$ 57,840
Restricted cash	5,475	2,167	2,316
Total cash, cash equivalents and restricted cash	$ 105,314	$ 17,874	$ 60,156	$ 78,155

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended		10 Months Ended	56 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 13, 2017	Jun. 30, 2021	Dec. 31, 2020
Cash investment in money market fund	$ 0				$ 1,000
Organization costs incurred			$ 243
Offering costs incurred				$ 15,229
Percentage of distribution of annual REIT taxable income to stockholders to qualify as REIT	90.00%
Unrecognized interest or penalties	$ 0	$ 0
Minimum Gross Proceeds From Public Offering To Charge Offering Costs	$ 250,000
Percentage of reimbursement revenue	0.75%
Accrued Unrecognised Interest or Penalties	$ 0

Loans Receivable - Summary of D

Loans Receivable - Summary of Details Overall Statistics for Loans Receivable Portfolio (Detail) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)Loans	Dec. 31, 2020USD ($)Loans	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)
Loans and Leases Receivable Disclosure [Line Items]
Number of loans | Loans	78	35
Principal balance	$ 2,511,999	$ 699,250
Net book value	2,511,901	700,149	$ 599,015	$ 406,645
Unfunded loan commitments	$ 185,674	$ 100,389
Weighted-average cash coupon	3.54%	4.25%
Weighted-average all-in yield	3.58%	4.35%
Weighted-average maximum maturity (years)	4 years 4 months 24 days	3 years 8 months 12 days

Loans Receivable - Summary of A

Loans Receivable - Summary of Activity in Loan Portfolio (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Loans and Leases Receivable Disclosure [Line Items]
Balance at beginning of period	$ 700,149	$ 406,645
Loan fundings	1,990,205	214,855
Loan repayments	(178,428)	(22,988)
Amortization of deferred fees on loans	702	680
Exit and extension fees received on loans	(727)	(167)
Balance at end of period	$ 2,511,901	$ 599,015

Loans Receivable - Loan Receiva

Loans Receivable - Loan Receivables Acquired By Property (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Net book value	$ 2,511,901	$ 700,149	$ 599,015	$ 406,645
Loan Receivable Held For Investment [Member]
Net book value	$ 2,511,901	$ 700,149
Percentage	100.00%	100.00%
Office [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 292,375	$ 174,483
Percentage	12.00%	25.00%
Industrial [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 305,172	$ 168,876
Percentage	12.00%	24.00%
Multifamily [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 1,518,516	$ 130,648
Percentage	60.00%	19.00%
Mixed-Use [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 112,578	$ 91,556
Percentage	4.00%	13.00%
Hospitality [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 63,422	$ 62,759
Percentage	3.00%	9.00%
Retail [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 55,283	$ 52,128
Percentage	2.00%	7.00%
Self Storage [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 164,555	$ 19,699
Percentage	7.00%	3.00%

Loans Receivable - Loan Recei_2

Loans Receivable - Loan Receivables Acquired By Geographics (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Net book value	$ 2,511,901	$ 700,149	$ 599,015	$ 406,645
Loan Receivable Held For Investment [Member]
Net book value	$ 2,511,901	$ 700,149
Percentage	100.00%	100.00%
South [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 1,400,387	$ 311,123
Percentage	56.00%	44.00%
West [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 475,730	$ 201,318
Percentage	19.00%	29.00%
Northeast [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 394,132	$ 168,009
Percentage	15.00%	24.00%
Midwest [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 221,952
Percentage	9.00%
Various [Member] | Loan Receivable Held For Investment [Member]
Net book value	$ 19,700	$ 19,699
Percentage	1.00%	3.00%

Loans Receivable - Summary of l

Loans Receivable - Summary of loans receivable based on internal risk ratings: (Detail) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)Loans	Dec. 31, 2020USD ($)Loans	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)
Loans Receivable Based On Internal Risk Ratings [Line Items]
Number of loans | Loans	78	35
Net book value | $	$ 2,511,901	$ 700,149	$ 599,015	$ 406,645
Loan Receivable Held For Investment [Member]
Loans Receivable Based On Internal Risk Ratings [Line Items]
Number of loans | Loans	78	35
Net book value | $	$ 2,511,901	$ 700,149
Percentage	100.00%	100.00%
Risk Level, Medium [Member] | Loan Receivable Held For Investment [Member]
Loans Receivable Based On Internal Risk Ratings [Line Items]
Number of loans | Loans	78	34
Net book value | $	$ 2,511,901	$ 689,104
Percentage	100.00%	98.00%
Risk Level, High [Member] | Loan Receivable Held For Investment [Member]
Loans Receivable Based On Internal Risk Ratings [Line Items]
Number of loans | Loans		1
Net book value | $		$ 11,045
Percentage		2.00%

Mortgage Backed Securities - Sc

Mortgage Backed Securities - Schedule of Available-for-sale Securities Reconciliation (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Outstanding Face Amount	$ 36,576	$ 25,555
Fair Value	$ 48,737		$ 0
Weighted Average Coupon	3.54%		4.25%
CMBS [Member]
Outstanding Face Amount	$ 48,664
Amortized Cost Basis	48,633
Gross Unrealize Gains	137
Gross Unrealized Losses	(33)
Fair Value	$ 48,737
Weighted Average Coupon	6.47%
Weighted Average Remaining Duration (years)	16 years 2 months 12 days

Mortgage Backed Securities - Su

Mortgage Backed Securities - Summary of Investment Held-to-maturity CMBS (Detail) - Commercial Mortgage Backed Securities - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]
Net Carrying Amount (Amortized Cost)	$ 37,723	$ 37,314
Fair Value	$ 37,723	$ 37,314

Mortgage Backed Securities - _2

Mortgage Backed Securities - Summary of Maturities of Investment Held-to-maturity CMBS (Detail) - Commercial Mortgage Backed Securities $ in Thousands	Sep. 30, 2021USD ($)
Schedule of Held-to-maturity Securities [Line Items]
CMBS, held-to-maturity, Total	$ 37,723
CMBS, held-to-maturity, 3-5 years	$ 37,723

Financing Arrangements - Summar

Financing Arrangements - Summary of Information of Outstanding Financing Arrangement (Detail) - USD ($) $ in Thousands	Jul. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 1,922,683	$ 453,125
Amount Available		307,848	174,540
Carrying Amount of Collateral		2,345,888	578,912
Fair Value of Collateral		2,349,711	576,469
Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		974,600
Carrying Amount of Collateral		1,204,940
Fair Value of Collateral		1,208,062
Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		908,083	125,460
Amount Available		92,848	149,540
Carrying Amount of Collateral		1,140,948	167,457
Fair Value of Collateral		1,141,649	166,972
Revolving Credit Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		40,000
Amount Available		215,000
2019-FLI Notes [Member] | Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 327,665	327,665
Amount Available			$ 0
Description of variable rate		L+1.20% — 2.50%	L+1.20% — 2.50%
Maturity Date		Dec. 18, 2036	Dec. 18, 2036
Carrying Amount of Collateral		$ 422,345	$ 411,455
Fair Value of Collateral		$ 423,079	$ 409,497
2019-FLI Notes [Member] | Maximum [Member] | Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		2.50	2.50
2019-FLI Notes [Member] | Minimum [Member] | Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		1.20	1.20
2021-FL2 Notes [Member] | Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 646,935
Description of variable rate		L+1.22% — 3.45%
Maturity Date		May 5, 2038
Carrying Amount of Collateral		$ 782,595
Fair Value of Collateral		$ 784,983
2021-FL2 Notes [Member] | Maximum [Member] | Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		3.45
2021-FL2 Notes [Member] | Minimum [Member] | Collateralized Loan Obligations [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		1.22
WF-1 Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Maturity Date	Aug. 30, 2022
WF-1 Facility [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 314,092	$ 29,889
Amount Available		$ 35,908	$ 70,111
Description of variable rate		L+2.15% — 2.50%	L+2.15% — 2.50%
Maturity Date		Aug. 30, 2022	Aug. 30, 2021
Carrying Amount of Collateral		$ 392,642	$ 39,945
Fair Value of Collateral		$ 392,816	$ 39,977
WF-1 Facility [Member] | Maximum [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		2.50	2.50
WF-1 Facility [Member] | Minimum [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		2.15	2.15
GS-1 Facility [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 151,257	$ 95,571
Amount Available		$ 23,743	$ 79,429
Description of variable rate		L+1.75% — 2.75%	L+1.75% — 2.75%
Maturity Date		Jan. 26, 2022	Jan. 26, 2021
Carrying Amount of Collateral		$ 190,981	$ 127,512
Fair Value of Collateral		$ 191,025	$ 126,995
GS-1 Facility [Member] | Maximum [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		2.75	2.75
GS-1 Facility [Member] | Minimum [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		1.75	1.75
BB-1 Facility [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 416,803
Amount Available		$ 33,197
Description of variable rate		L+1.55% — 1.95%
Maturity Date		Feb. 22, 2024
Carrying Amount of Collateral		$ 520,745
Fair Value of Collateral		$ 521,125
BB-1 Facility [Member] | Maximum [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		1.95
BB-1 Facility [Member] | Minimum [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Basis for effective rate		1.55
RBC Facility [Member] | Repurchase Agreements [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		$ 25,931
Description of variable rate		L+1.35%
Basis for effective rate		1.35
Carrying Amount of Collateral		$ 36,580
Fair Value of Collateral		36,683
City National Bank Facility [Member] | Revolving Credit Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Outstanding		40,000	$ 0
Amount Available		$ 15,000	$ 25,000
Description of variable rate		L+2.25%	L+2.25%
Basis for effective rate		2.25	2.25
Maturity Date		Jun. 7, 2023	Aug. 23, 2022
Carrying Amount of Collateral			$ 0
Fair Value of Collateral			$ 0
MM-1 Facility | Revolving Credit Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Amount Available		$ 200,000
Description of variable rate		L+2.10
Basis for effective rate		2.10
Maturity Date		Sep. 20, 2029

Financing Arrangements - Summ_2

Financing Arrangements - Summary of Information of Outstanding Financing Arrangement (Parenthetical) (Detail) - London Interbank Offered Rate (LIBOR) [Member]	9 Months Ended
	Sep. 30, 2021
Assets Sold under Agreements to Repurchase [Line Items]
LIBOR rate	0.00
WF-1 Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
LIBOR rate	0.00
GS-1 Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
LIBOR rate	0.50
BB-1 Facility [Member]
Assets Sold under Agreements to Repurchase [Line Items]
LIBOR rate	0.50

Financing Arrangements - Additi

Financing Arrangements - Additional Information (Detail)

Sep. 20, 2021USD ($)

Jul. 30, 2021USD ($)

Feb. 22, 2021USD ($)Extension

Sep. 30, 2021USD ($)

Dec. 31, 2020USD ($)

Aug. 05, 2021USD ($)

Jul. 07, 2021USD ($)

Jul. 06, 2021USD ($)

May 05, 2021USD ($)

Apr. 26, 2021USD ($)

Apr. 23, 2021USD ($)

Dec. 05, 2019USD ($)

Assets Sold under Agreements to Repurchase [Line Items]

Maximum amount of financing available

$ 264,000,000

Deferred financing costs

$ 2,761,000

$ 152,000

Line of credit facility maximum borrowing capacity decrease

368,755,000

66,633,000

Extended Date [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Debt Instrument, Maturity Date

Aug. 30, 2021

Amendment To Credit Facility With Barclays [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Maximum amount of financing available

$ 450,000,000

Collateralized Loan Obligations [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Deferred financing costs

10,166,000

4,556,000

Amortization expense od debt issuance cost

3,691,000

Collateralized Loan Obligations [Member] | Two Three commercial estate loans [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Securities collatered against loans

422,359,000

Collateralized Loan Obligations [Member] | Two Nine Commercial Estate Loan [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Securities collatered against loans

$ 782,913,000

SubREIT [Member] | Collateralized Loan Obligations [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Total Debt financing cost

$ 327,665,000

LIBOR [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Description of variable rate

0.00

WF-1 Facility [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Average borrowings

$ 1,011,011,000

$ 413,236,000

Maximum amount of financing available

200,000,000

$ 100,000,000

Increase in amount of financing available

$ 350,000,000

350,000,000

Deferred financing costs

$ 865,000

Weighted Average Rate

1.70%

2.12%

Debt Instrument, Maturity Date

Aug. 30, 2022

Number of funding years extended

1 year

Number of maturity years extended

3 years

WF-1 Facility [Member] | LIBOR [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Description of variable rate

0.00

WF-1 Facility [Member] | Minimum [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Line of credit facility maximum borrowing capacity decrease

$ 150,000,000

WF-1 Facility [Member] | Maximum [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Line of credit facility maximum borrowing capacity decrease

350,000,000

GS-1 Facility [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Maximum amount of financing available

$ 175,000,000

Increase in amount of financing available

250,000,000

Deferred financing costs

$ 224,000

GS-1 Facility [Member] | LIBOR [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Description of variable rate

0.50

BB-1 Facility [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Maximum amount of financing available

$ 175,000,000

Increase in amount of financing available

$ 264,000,000

$ 264,000,000

$ 250,000,000

$ 175,828,000

Funding period and term of facility

3 years

Number of extensions of funding period | Extension

2

Extension period of funding

1 year

Deferred financing costs

$ 984,000

BB-1 Facility [Member] | LIBOR [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Description of variable rate

0.50

City National Bank Facility [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Maximum amount of financing available

$ 55,000,000

$ 55,000,000

25,000,000

Deferred financing costs

$ 458,000

Minimum Net Asset Value

$ 275,000,000

$ 175,000,000

City National Bank Facility [Member] | LIBOR [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Unused capacity commitment fee percentage

0.375%

Description of variable rate

LIBOR plus a spread of 2.25%

Spread on LIBOR

2.25%

2021-FL2 Notes [Member] | Collateralized Loan Obligations [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Deferred financing costs

$ 6,475,000

2021-FL2 Notes [Member] | SubREIT [Member] | Collateralized Loan Obligations [Member]

Assets Sold under Agreements to Repurchase [Line Items]

Total Debt financing cost

$ 646,935,000

MM-1 Facility

Assets Sold under Agreements to Repurchase [Line Items]

Maximum amount of financing available

$ 200,000,000

Increase in amount of financing available

$ 250,000,000

Unused capacity commitment fee percentage

85.00%

Debt Issuance Costs, Gross

$ 2,303,000

Line of Credit Facility, Interest Rate at Period End

2.10%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	Nov. 01, 2020	Feb. 14, 2020	Dec. 08, 2016	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Sep. 30, 2021	Aug. 10, 2021	Oct. 25, 2019
Related Party Transaction [Line Items]
Performance fee percentage						10.00%
Hurdle rate on average adjusted capital						1.625%
Annualized hurdle rate						6.50%
Quarterly core earnings rate						1.806%
Annualized core earnings rate						7.222%
Reimbursement due from sponsor				$ 0		$ 0		$ 444,000	$ 0
Common stock allocated to investors											$ 21,400,000
Investments to be maintained				10,000,000		10,000,000			10,000,000
Due to Related Parties				$ 36,131,000		$ 36,131,000		15,481,000	36,131,000
Stock Repurchased During Period, Shares				165,004	132,745	375,041	943,601
Stock Repurchased During Period, Value				$ 4,121,000	$ 3,338,000	$ 9,354,000	$ 23,517,000
Organization and offering costs									$ 15,472,000
Recoupment Payable						8,000		0
Recoupment Amount						3,736,000
Common Class Y [Member]
Related Party Transaction [Line Items]
Base management fee						0
Class D, Class M, Class I, Class F Or Class Y Shares [Member]
Related Party Transaction [Line Items]
Selling commissions or dealer manager fees payable						0
Common Class F [Member]
Related Party Transaction [Line Items]
Base management fee						$ 0
Performance fee percentage						0.00%
Maximum [Member]
Related Party Transaction [Line Items]
Organization and offering expenses reimbursement as percentage of gross proceeds from public offering				15.00%		15.00%			15.00%
FS Real Estate Advisor [Member]
Related Party Transaction [Line Items]
Base management fee percentage						1.25%
Base management fee description						equal to 1.25% of the NAV for the Company’s Class T, Class S, Class D, Class M and Class I shares, payable quarterly in arrears
Minimum gross proceeds from public offering to reimburse expense						$ 250,000,000
Organization and offering expenses reimbursement as percentage of gross proceeds from public offering				0.75%		0.75%			0.75%
FS Real Estate Advisor [Member] | Expense Limitation [Member]
Related Party Transaction [Line Items]
Percentage of minimum operating expenses to be waived or paid						1.50%
FS Real Estate Advisor [Member] | Common Class S [Member]
Related Party Transaction [Line Items]
Dealer manager upfront selling commissions fees percentage						3.50%
Stockholders servicing fee percentage on aggregate NAV of outstanding shares						0.85%
Stockholder servicing fees percentage				8.75%		8.75%			8.75%
FS Real Estate Advisor [Member] | Common Class T [Member]
Related Party Transaction [Line Items]
Dealer manager upfront selling commissions fees percentage						3.00%
Upfront dealer manager fees percentage						0.50%
Stockholders servicing fee percentage on aggregate NAV of outstanding shares						0.85%
Advisor stockholders servicing fee percentage on aggregate NAV of outstanding shares						0.65%
Dealer stockholders servicing fee percentage on aggregate NAV of outstanding shares						0.20%
Stockholder servicing fees percentage				8.75%		8.75%			8.75%
Selling commission and fee maximum percent						3.50%
FS Real Estate Advisor [Member] | Common Class D [Member]
Related Party Transaction [Line Items]
Stockholders servicing fee percentage on aggregate NAV of outstanding shares						0.30%
Stockholder servicing fees percentage				1.25%		1.25%			1.25%
FS Real Estate Advisor [Member] | Common Class M [Member]
Related Party Transaction [Line Items]
Stockholders servicing fee percentage on aggregate NAV of outstanding shares						0.30%
Stockholder servicing fees percentage				7.25%		7.25%			7.25%
FS Real Estate Advisor [Member] | Class T, Class T-C and Class M Shares [Member]
Related Party Transaction [Line Items]
Stockholder servicing fees percentage				10.00%		10.00%			10.00%
FS Real Estate Advisor [Member] | Common Class F [Member]
Related Party Transaction [Line Items]
Investments Owned										$ 21,425,000
FS Real Estate Advisor [Member] | Class T, Class S, Class D and Class M Share [Member]
Related Party Transaction [Line Items]
Stockholder servicing fees percentage				10.00%		10.00%			10.00%
FS Real Estate Advisor [Member] | Maximum [Member] | Expense Limitation [Member]
Related Party Transaction [Line Items]
Period for which reimbursement payable						3 years
FS Real Estate Advisor and Rialto [Member]
Related Party Transaction [Line Items]
Reimbursement expenses due from sponsor						$ 56,000
Amount received as reimbursement						5,839,000
Due to Related Parties				$ 14,146,000		14,146,000			$ 14,146,000
Recoupment Payable						390,000
Rialto [Member]
Related Party Transaction [Line Items]
Purchase of floating-rate whole mortgage loan						5,839,000
FS Investments and Rialto [Member]
Related Party Transaction [Line Items]
Due to Related Parties				$ 36,122,000		$ 36,122,000		$ 15,481,000	$ 36,122,000
FS Investments and Rialto [Member] | Private Placement [Member]
Related Party Transaction [Line Items]
Aggregate proceeds from private placement			$ 200,000
Number of common shares issued			8,000
Common stock, price per share				$ 25		$ 25			$ 25
FS Investments and Rialto [Member] | Common Class S [Member] | Private Placement [Member]
Related Party Transaction [Line Items]
Additional Purchase Commitment Period	expired on November 1, 2020
FS Investments and Rialto [Member] | Common Class F [Member]
Related Party Transaction [Line Items]
Repurchase of shares											$ 17,000,000
Share price per share								$ 24.95
FS Investments and Rialto [Member] | Common Class F [Member] | Private Placement [Member]
Related Party Transaction [Line Items]
Net assets				$ 750,000		$ 750,000			$ 750,000
MCFDA SCV LLC [Member] | Common Class F [Member]
Related Party Transaction [Line Items]
Repurchase of shares		$ 14,700,000
Share price per share		$ 24.95

Related Party Transactions - Su

Related Party Transactions - Summary of Fees and Expenses Accrued under Advisory Agreement (Detail) - Fs Real Estate Advisor [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Base Management Fees [Member]
Related Party Transaction [Line Items]
FS Real Estate Advisor	$ 1,944	$ 760	$ 4,269	$ 2,076
Performance Fees [Member]
Related Party Transaction [Line Items]
FS Real Estate Advisor	8	465	968	903
Administrative Services Expenses [Member]
Related Party Transaction [Line Items]
FS Real Estate Advisor	$ 1,260	$ 810	$ 2,708	$ 1,698

Related Party Transactions - _2

Related Party Transactions - Summary of Fees and Expenses Accrued under Advisory Agreement (Parenthetical) (Detail) - Fs Real Estate Advisor [Member] - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Management Fee Payable	$ 1,944		$ 869
Base Management Fees [Member]
Related Party Transaction [Line Items]
Fees and expenses accrued	3,194	$ 1,642
Performance Fee Payable	8		$ 316
Performance Fees [Member]
Related Party Transaction [Line Items]
Fees and expenses accrued	1,276	438
Administrative Services Expenses [Member]
Related Party Transaction [Line Items]
Fees and expenses accrued	$ 2,448	$ 1,610

Related Party Transactions - _3

Related Party Transactions - Summary of reimbursed by FS Real Estate (Detail) - USD ($) $ in Thousands	3 Months Ended															9 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2021
Schedule Of Expense Reimbursed [Line Items]
Expense Reimbursement	$ 56	$ 444	$ 397	$ 182		$ 500	$ 491	$ 420	$ 537	$ 709	$ 645	$ 561	$ 356	$ 377	$ 164	$ 5,839
Recoupable Amount	$ 56	$ 444	$ 397	$ 182		$ 500	$ 491	$ 420	$ 537	$ 709						3,736
Recoupment eligibility expiration	March 31, 2023	December 31, 2023	September 30, 2023	June 30, 2023		December 31, 2022	September 30, 2022	June 30, 2022	March 31, 2022	December 31, 2021	September 30, 2021	June 30, 2021	March 31, 2021	December 31, 2020	September 30, 2020
Recoupment Paid Or Payable											$ 8	$ 390				398
Recoupment Expired Amount											$ 637	$ 171	$ 356	$ 377	$ 164	$ 1,705

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Common Stock Transactions (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Class of Stock [Line Items]
Balance at beginning of period, amount	$ 483,487	$ 240,411	$ 305,712	$ 165,787
Issuance of common stock, amount	272,129	23,393	460,045	137,348
Reinvestment of distributions, amount	4,448	1,365	9,603	3,706
Redemptions of common stock, amount	(4,121)	(3,338)	(9,354)	(38,184)
Balance at end of period, amount	742,796	262,340	742,796	262,340
Common Class F [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	9	9	9	15
Redemptions of common stock, amount				(6)
Balance at end of period, amount	9	9	9	9
Common Class Y [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	9	1	1	1
Issuance of common stock, amount			9
Redemptions of common stock, amount			(1)
Balance at end of period, amount	9	1	9	1
Common Class T [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	13	12	12	10
Issuance of common stock, amount			1	2
Balance at end of period, amount	13	12	13	12
Common Class S [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	101	41	58	14
Issuance of common stock, amount	61	5	103	34
Reinvestment of distributions, amount	1		2
Redemptions of common stock, amount	(1)	(1)	(1)	(3)
Balance at end of period, amount	162	45	162	45
Common Class D [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	6	5	5	3
Issuance of common stock, amount			1	3
Balance at end of period, amount	6	6	6	6
Common Class M [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	24	17	20	14
Issuance of common stock, amount	4	1	9	6
Redemptions of common stock, amount		0	(1)	(2)
Balance at end of period, amount	28	18	28	18
Common Class I [Member]
Class of Stock [Line Items]
Balance at beginning of period, amount	41	15	22	12
Issuance of common stock, amount	44	3	61	10
Reinvestment of distributions, amount			2
Redemptions of common stock, amount	(1)	0	(1)	(4)
Balance at end of period, amount	$ 84	$ 18	$ 84	$ 18
Common Stock [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			12,762,748	6,860,474
Issuance of common stock, shares			18,408,563	5,453,100
Reinvestment of distributions, shares			382,590	147,801
Redemptions of common stock, shares			(375,041)	(1,531,336)
Transfers in or out, shares			3,525	338
Balance at end of period, shares	31,182,385	10,930,377	31,182,385	10,930,377
Balance at beginning of period, amount			$ 303,827	$ 165,151
Issuance of common stock, amount			460,045	137,348
Reinvestment of distributions, amount			9,603	3,706
Redemptions of common stock, amount			(9,354)	(38,184)
Accrued stockholder servicing fees, amount			(22,399)	(7,471)
Transfers in or out, amount			0
Balance at end of period, amount	$ 741,722	$ 260,550	$ 741,722	$ 260,550
Common Stock [Member] | Common Class F [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			912,469	1,475,155
Issuance of common stock, shares			0
Reinvestment of distributions, shares			23,310	21,354
Redemptions of common stock, shares			(33,638)	(591,722)
Transfers in or out, shares			(6,392)
Balance at end of period, shares	895,749	904,787	895,749	904,787
Balance at beginning of period, amount			$ 22,378	$ 36,419
Issuance of common stock, amount			0
Reinvestment of distributions, amount			585	532
Redemptions of common stock, amount			(843)	(14,766)
Accrued stockholder servicing fees, amount			0
Transfers in or out, amount			(160)
Balance at end of period, amount	$ 21,960	$ 22,185	$ 21,960	$ 22,185
Common Stock [Member] | Common Class Y [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			137,116	141,116
Issuance of common stock, shares			843,659
Reinvestment of distributions, shares			0
Redemptions of common stock, shares			(74,127)
Transfers in or out, shares			0
Balance at end of period, shares	906,648	141,116	906,648	141,116
Balance at beginning of period, amount			$ 3,449	$ 3,548
Issuance of common stock, amount			20,749
Reinvestment of distributions, amount			0
Redemptions of common stock, amount			(1,827)
Accrued stockholder servicing fees, amount			0
Transfers in or out, amount			0
Balance at end of period, amount	$ 22,371	$ 3,548	$ 22,371	$ 3,548
Common Stock [Member] | Common Class T [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			1,245,658	981,836
Issuance of common stock, shares			96,414	248,615
Reinvestment of distributions, shares			29,916	25,610
Redemptions of common stock, shares			(27,614)	(42,441)
Transfers in or out, shares			(3,664)
Balance at end of period, shares	1,340,710	1,213,620	1,340,710	1,213,620
Balance at beginning of period, amount			$ 29,971	$ 23,616
Issuance of common stock, amount			2,419	6,253
Reinvestment of distributions, amount			750	643
Redemptions of common stock, amount			(692)	(1,067)
Accrued stockholder servicing fees, amount			(87)	(257)
Transfers in or out, amount			(92)
Balance at end of period, amount	$ 32,269	$ 29,188	$ 32,269	$ 29,188
Common Stock [Member] | Common Class S [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			5,778,640	1,351,587
Issuance of common stock, shares			10,303,946	3,342,412
Reinvestment of distributions, shares			214,826	46,607
Redemptions of common stock, shares			(86,170)	(284,499)
Transfers in or out, shares			(1,684)
Balance at end of period, shares	16,209,558	4,456,107	16,209,558	4,456,107
Balance at beginning of period, amount			$ 134,705	$ 31,429
Issuance of common stock, amount			260,437	84,726
Reinvestment of distributions, amount			5,429	1,178
Redemptions of common stock, amount			(2,177)	(7,184)
Accrued stockholder servicing fees, amount			(20,817)	(6,351)
Transfers in or out, amount			(43)
Balance at end of period, amount	$ 377,534	$ 103,798	$ 377,534	$ 103,798
Common Stock [Member] | Common Class D [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			546,298	322,602
Issuance of common stock, shares			129,097	240,665
Reinvestment of distributions, shares			9,827	7,472
Redemptions of common stock, shares			(14,551)	(10,304)
Transfers in or out, shares			(50,714)
Balance at end of period, shares	619,957	560,435	619,957	560,435
Balance at beginning of period, amount			$ 13,573	$ 8,015
Issuance of common stock, amount			3,242	6,054
Reinvestment of distributions, amount			247	188
Redemptions of common stock, amount			(365)	(259)
Accrued stockholder servicing fees, amount			(27)	(73)
Transfers in or out, amount			(1,274)
Balance at end of period, amount	$ 15,396	$ 13,925	$ 15,396	$ 13,925
Common Stock [Member] | Common Class M [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			1,971,039	1,357,818
Issuance of common stock, shares			953,885	642,576
Reinvestment of distributions, shares			36,910	24,494
Redemptions of common stock, shares			(71,799)	(205,668)
Transfers in or out, shares			(85,401)	(14,283)
Balance at end of period, shares	2,804,634	1,804,937	2,804,634	1,804,937
Balance at beginning of period, amount			$ 46,154	$ 31,757
Issuance of common stock, amount			23,996	16,202
Reinvestment of distributions, amount			929	617
Redemptions of common stock, amount			(1,804)	(5,175)
Accrued stockholder servicing fees, amount			(1,468)	(790)
Transfers in or out, amount			(2,145)	(361)
Balance at end of period, amount	$ 65,662	$ 42,250	$ 65,662	$ 42,250
Common Stock [Member] | Common Class I [Member]
Class of Stock [Line Items]
Balance at beginning of period, shares			2,171,528	1,230,360
Issuance of common stock, shares			6,081,562	978,832
Reinvestment of distributions, shares			67,801	22,264
Redemptions of common stock, shares			(67,142)	(396,702)
Transfers in or out, shares			151,380	14,621
Balance at end of period, shares	8,405,129	1,849,375	8,405,129	1,849,375
Balance at beginning of period, amount			$ 53,597	$ 30,367
Issuance of common stock, amount			149,202	24,113
Reinvestment of distributions, amount			1,663	548
Redemptions of common stock, amount			(1,646)	(9,733)
Accrued stockholder servicing fees, amount			0
Transfers in or out, amount			3,714	361
Balance at end of period, amount	$ 206,530	$ 45,656	$ 206,530	$ 45,656

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Percentage limited to repurchase of shares to NAV of all classes of shares			20.00%
Shares repurchased under repurchase plan	165,004	132,745	375,041	943,601
Shares repurchased under repurchase plan, value	$ 4,121	$ 3,338	$ 9,354	$ 23,517
Unfulfilled repurchase requests			0	179,318
Maximum [Member]
Repurchase of shares to NAV of all classes of shares, percentage			5.00%
Series A Preferred Stock [Member]
Preferred Stock, Dividend Rate			12.00%

Stockholders' Equity - Summar_2

Stockholders' Equity - Summary of Cash Distributions Per Share that Paid on its Common Stock (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended									3 Months Ended		9 Months Ended
	Sep. 29, 2021	Aug. 30, 2021	Jul. 29, 2021	Jun. 29, 2021	May 27, 2021	Apr. 29, 2021	Mar. 30, 2021	Feb. 25, 2021	Jan. 28, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Distributions:
Paid or payable in cash										$ 6,505	$ 2,912	$ 14,861	$ 7,993
Reinvested in shares										4,448	1,365	9,603	3,706
Total distributions										10,953	4,277	24,464	11,699
Cash flows from operating activities										10,953	4,277	24,464	11,699
Total sources of distributions										10,953	4,277	24,464	11,699
Net cash provided by operating activities										$ 10,275	$ 4,904	$ 27,591	$ 18,993
Common Class F [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	$ 0.1710	$ 0.1710	$ 0.1710	$ 0.1710	$ 0.1710	$ 0.1710	$ 0.1710	$ 0.1710	$ 0.1710			$ 1.5390
Common Class Y [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	0.1710	0.1710	0.1710	0.1710	0.1710	0.1710	0.1710	0.1710	0.1710			1.5390
Common Class T [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273			1.1457
Common Class S [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273	0.1273			1.1457
Common Class D [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388			1.2492
Common Class M [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388	0.1388			1.2492
Common Class I [Member]
Dividends Payable [Line Items]
Distributions paid per share of common stock	$ 0.1450	$ 0.1450	$ 0.1450	$ 0.1450	$ 0.1450	$ 0.1450	$ 0.1450	$ 0.1450	$ 0.1450			$ 1.3050

Stockholders' Equity - Summar_3

Stockholders' Equity - Summary of Cash Distributions Per Share that Paid on its Common Stock (Detail) (Parenthetical) $ in Thousands	3 Months Ended
	Sep. 30, 2021USD ($)
Related Party Transactions [Abstract]
Cash flow from operating activities, including cash	$ 678

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Cash Distribution On Class of Common Stock (Detail)	1 Months Ended
	Oct. 31, 2021$ / shares
Common Class F [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	$ 0.1610
Common Class Y [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	0.1610
Common Class T [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	0.1173
Common Class S [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	0.1173
Common Class D [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	0.1288
Common Class M [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	0.1288
Common Class I [Member]
Class of Stock [Line Items]
Distributions declared per share for each class of outstanding common stock	$ 0.1350

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Summary Of Company Financial Instruments Carried At Fair Value In The Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Mortgage-backed securities available for sale	$ 48,737	$ 0
Fair Value, Inputs, Level 1 [Member]
Mortgage-backed securities available for sale	0	0
Fair Value, Inputs, Level 2 [Member]
Mortgage-backed securities available for sale	48,737	0
Fair Value, Inputs, Level 3 [Member]
Mortgage-backed securities available for sale	$ 0	$ 0

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Summary of Carrying Amount, Face Amount, and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed securities held-to-maturity		$ 37,723	$ 37,314
Collateralized loan obligations		964,434	323,109
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash		105,314	17,874
Loans receivable - held-for-investment	[1]	2,511,901	700,149
Mortgage-backed securities held-to-maturity		37,723	37,314
Repurchase obligations	[2]	906,010	125,266
Credit facility		40,000
Collateralized loan obligations	[2]	964,434	323,109
Portion at Other than Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash		105,314	17,874
Loans receivable - held-for-investment	[1]	2,511,999	699,250
Mortgage-backed securities held-to-maturity		50,300	50,300
Repurchase obligations	[2]	908,083	125,460
Credit facility		40,000
Collateralized loan obligations	[2]	974,600	327,665
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash		105,314	17,874
Loans receivable - held-for-investment	[1]	2,515,244	697,533
Mortgage-backed securities held-to-maturity		37,723	37,314
Repurchase obligations	[2]	908,083	125,460
Credit facility		40,000
Collateralized loan obligations	[2]	$ 974,600	$ 327,665
[1]	Book value of loans receivable represents the face amount, net of unamortized loan fees and costs and accrual of exit fees, as applicable.
[2]	Book value represents the face amount, net of deferred financing costs.

Variable Interest Entities - Sc

Variable Interest Entities - Schedule of detailed information about the assets and liabilities (Details) - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entity [Line Items]
VIE Assets	[1]	$ 2,712,200	$ 774,979
VIE Liabilities	[1]	1,969,404	469,267
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Assets		1,212,364	429,771
VIE Liabilities		965,277	323,336
Restricted cash [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Assets		3,938	4
Loans receivable, held-for-investment [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Assets		1,204,940	411,455
Interest receivable [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Assets		3,486	2,470
Other Assets [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Assets			15,842
Collateralized loan obligations [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Liabilities		964,434	323,109
Interest payable [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Liabilities		638	$ 227
Other liabilities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
VIE Liabilities		$ 205
[1]	The September 30, 2021 and December 31, 2020 consolidated balance sheets include assets of consolidated variable interest entities, or VIEs, that can only be used to settle obligations of the VIEs, and liabilities of consolidated VIEs for which creditors do not have recourse to the Company. As of September 30, 2021 and December 31, 2020, assets of the VIEs totaled $1,212,364 and $429,771, respectively, and liabilities of the VIEs totaled $965,277 and $323,336, respectively. See Note 9 to the unaudited consolidated financial statements for further details.

Variable Interest Entities - _2

Variable Interest Entities - Schedule of detailed information about the assets and liabilities (Parenthetical) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Deferred financing cost [Member]
Variable Interest Entity [Line Items]
Deferred Offering Costs	$ 10,166	$ 4,556

Variable Interest Entities - Ad

Variable Interest Entities - Additional Information (Detail) - Variable Interest Entity, Not Primary Beneficiary [Member] - Commercial Mortgage Backed Securities $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Variable Interest Entity [Line Items]
Payments to Acquire Equity Method Investments	$ 37,005
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 37,723

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Nov. 08, 2021	Nov. 04, 2021	Nov. 08, 2021	Sep. 30, 2021	Sep. 30, 2020	Oct. 31, 2021	Dec. 31, 2020
Subsequent Event [Line Items]
Common stock shares issued				$ 460,045	$ 137,348
Line of credit facility maximum borrowing capacity decrease				$ 368,755			$ 66,633
Proceeds from public offerings			$ 81,869
Preferred Stock, Shares Issued				125			0
Preferred Stock, Par or Stated Value Per Share				$ 0.01			$ 0.01
Common Class F [Member]
Subsequent Event [Line Items]
Common stock, shares issued				895,749			912,469
Common Class Y [Member]
Subsequent Event [Line Items]
Common stock, shares issued				906,648			137,116
Common Class T [Member]
Subsequent Event [Line Items]
Common stock, shares issued				1,340,710			1,245,658
Common Class S [Member]
Subsequent Event [Line Items]
Common stock, shares issued				16,209,558			5,778,640
Common Class D [Member]
Subsequent Event [Line Items]
Common stock, shares issued				619,957			546,298
Common Class M [Member]
Subsequent Event [Line Items]
Common stock, shares issued				2,804,634			1,971,039
Common Class I [Member]
Subsequent Event [Line Items]
Common stock, shares issued				8,405,129			2,171,528
Subsequent Event [Member]
Subsequent Event [Line Items]
Common stock, shares issued	40,255,586		40,255,586
Common stock shares issued	$ 730,738
Subsequent Event [Member] | Class C Fourth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		$ 69,459
Subsequent Event [Member] | Minimum [Member] | Class C Fourth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2026
Debt Instrument, Interest Rate, Stated Percentage		0.50%
Subsequent Event [Member] | Maximum [Member] | Class C Fourth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		2.05%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		$ 928,483
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | FS Rialto 2021FL3 Holder, LLC [Member]
Subsequent Event [Line Items]
Percentage of Voting Interests Acquired		100.00%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | CLO3 Issuer [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class A Senior Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		$ 657,736
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class AS Second Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		42,526
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class B Third Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		55,283
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class D Fifth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		80,799
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class E Sixth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		22,680
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class F Seventh Priority Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		$ 66,624
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		4.50%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Class G Eighth Priority Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		$ 39,690
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		6.75%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Minimum [Member] | Class A Senior Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2026
Debt Instrument, Interest Rate, Stated Percentage		0.25%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Minimum [Member] | Class AS Second Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2026
Debt Instrument, Interest Rate, Stated Percentage		0.25%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Minimum [Member] | Class B Third Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2026
Debt Instrument, Interest Rate, Stated Percentage		0.50%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Minimum [Member] | Class D Fifth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2026
Debt Instrument, Interest Rate, Stated Percentage		0.50%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Minimum [Member] | Class E Sixth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2026
Debt Instrument, Interest Rate, Stated Percentage		0.50%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Maximum [Member] | Class A Senior Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		1.25%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Maximum [Member] | Class AS Second Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		1.55%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Maximum [Member] | Class B Third Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		1.80%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Maximum [Member] | Class D Fifth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		2.50%
Subsequent Event [Member] | Two Thousand Twenty One FL3 Notes [Member] | Maximum [Member] | Class E Sixth Priority Secured Floating Rate Notes [Member]
Subsequent Event [Line Items]
Debt instrument maturity year		2036
Debt Instrument, Interest Rate, Stated Percentage		2.85%
Subsequent Event [Member] | Common Class F [Member]
Subsequent Event [Line Items]
Common stock, shares issued	2,613,583		2,613,583
Subsequent Event [Member] | Common Stock [Member]
Subsequent Event [Line Items]
Number of Common Stock Repurchased						238,300
Share Repurchased, Amount						$ 5,853
Subsequent Event [Member] | Common Class Y [Member]
Subsequent Event [Line Items]
Common stock, shares issued	1,036,671		1,036,671
Subsequent Event [Member] | Common Class T [Member]
Subsequent Event [Line Items]
Common stock, shares issued	1,463,744		1,463,744
Subsequent Event [Member] | Common Class S [Member]
Subsequent Event [Line Items]
Common stock, shares issued	20,280,778		20,280,778
Subsequent Event [Member] | Common Class D [Member]
Subsequent Event [Line Items]
Common stock, shares issued	736,287		736,287
Subsequent Event [Member] | Common Class M [Member]
Subsequent Event [Line Items]
Common stock, shares issued	3,434,785		3,434,785
Subsequent Event [Member] | Common Class I [Member]
Subsequent Event [Line Items]
Common stock, shares issued	10,689,738		10,689,738
Subsequent Event [Member] | CLO3 Preferred Shares [Member]
Subsequent Event [Line Items]
Preferred Stock, Shares Issued		99,231
Preferred Stock, Par or Stated Value Per Share		$ 0.001
Preferred Stock, Liquidation Preference Per Share		$ 1,000