Portfolio Investments - Composition of Investment Portfolio (Details) - USD ($) $ in Thousands		Sep. 30, 2022		Jun. 30, 2022
Schedule of Investments [Line Items]
Cost		$ 7,345,486	[1],[2]	$ 7,196,831
Fair Value	[3]	7,582,665	[1],[2]	7,602,510
First Lien Revolving Line of Credit
Schedule of Investments [Line Items]
Cost		40,875		39,775
Fair Value		40,751		39,746
First Lien Debt
Schedule of Investments [Line Items]
Cost		3,980,337		3,839,553
Fair Value		3,884,792		3,757,960
Second Lien Debt
Schedule of Investments [Line Items]
Cost		1,593,464		1,588,557
Fair Value		1,441,284		1,471,336
Unsecured Debt
Schedule of Investments [Line Items]
Cost		7,200		7,200
Fair Value		7,200		7,200
Subordinated Structured Notes
Schedule of Investments [Line Items]
Cost		990,723		997,703
Fair Value		695,292		711,429
Equity
Schedule of Investments [Line Items]
Cost		732,887		724,043
Fair Value		$ 1,513,346		$ 1,614,839

[1] The following shows the composition of our investment portfolio at cost by control designation, investment type and by industry as of September 30, 2022: Industry1st Lien
Term Loan2nd Lien
Term LoanSubordinated Structured NotesUnsecured Debt Equity (B) Cost TotalControl InvestmentsAerospace & Defense$54,797 $— $— $— $55,581 $110,378 Commercial Services & Supplies124,680 — — 7,200 27,349 159,229 Construction & Engineering56,753 — — — 11,550 68,303 Consumer Finance452,388 — — — 81,303 533,691 Diversified Consumer Services— — — — 2,378 2,378 Energy Equipment & Services81,566 — — — 221,150 302,716 Equity Real Estate Investment Trusts (REITs)651,586 — — — 15,430 667,016 Health Care Providers & Services278,429 — — — 45,118 323,547 Machinery33,622 — — — 6,866 40,488 Media29,723 — — — — 29,723 Online Lending25,080 — — — — 25,080 Personal Products73,104 — — — 189,295 262,399 Trading Companies & Distributors32,708 — — — 32,500 65,208 Structured Finance (A)196,200 — — — — 196,200 Total Control Investments$2,090,636 $— $— $7,200 $688,520 $2,786,356 Affiliate InvestmentsCommercial Services & Supplies$— $— $— $— $9,523 $9,523 Diversified Consumer Services70,639 153,931 — — — 224,570 Textiles, Apparel & Luxury Goods— — — — 2,805 2,805  Total Affiliate Investments $70,639 $153,931 $— $— $12,328 $236,898 Non-Control/Non-Affiliate InvestmentsAir Freight & Logistics$92,620 $95,000 $— $— $— $187,620 Auto Components22,348 112,179 — — — 134,527 Building Products— 35,000 — — — 35,000 Capital Markets— 42,500 — — — 42,500 Commercial Services & Supplies68,786 185,304 — — 1,500 255,590 Communications Equipment9,214 50,585 — — — 59,799 Consumer Finance47,028 — — — — 47,028 Distributors168,207 103,730 — — — 271,937 Diversified Consumer Services— 22,713 — — — 22,713 Diversified Financial Services36,816 — — — — 36,816 Diversified Telecommunication Services44,266 121,799 — — — 166,065 Food & Staples Retailing27,437 — — — — 27,437 Food Products— 131,036 — — — 131,036 Health Care Equipment & Supplies— 7,484 — — — 7,484 Health Care Providers & Services181,414 159,664 — — 1,546 342,624 Health Care Technology128,973 — — — — 128,973 Hotels, Restaurants & Leisure23,127 — — — — 23,127 Household Durables96,475 29,777 — — 2,001 128,253 Household Products20,874 — — — — 20,874 Interactive Media & Services226,054 — — — — 226,054 Internet & Direct Marketing Retail20,217 — — — — 20,217 IT Services211,406 147,925 — — — 359,331 Leisure Products67,879 — — — 1 67,880 Machinery57,749 9,983 — — — 67,732 Media51,098 — — — 26,991 78,089 Pharmaceuticals25,536 — — — — 25,536 Professional Services66,785 123,606 — — — 190,391  Industry1st Lien
Term Loan2nd Lien
Term LoanSubordinated Structured NotesUnsecured Debt Equity (B) Cost TotalSoftware— 52,309 — — — 52,309 Textiles, Apparel & Luxury Goods165,628 8,939 — — — 174,567 Structured Finance (A)— — 990,723 — — 990,723  Total Non-Control/Non-Affiliate $1,859,937 $1,439,533 $990,723 $— $32,039 $4,322,232 Total Portfolio Investment Cost$4,021,212 $1,593,464 $990,723 $7,200 $732,887 $7,345,486  The following table shows the composition of our investment portfolio at fair value by control designation, investment type and by industry as of September 30, 2022: Industry1st Lien
Term Loan2nd Lien
Term LoanSubordinated Structured NotesUnsecured Debt Equity (B) Fair Value TotalFair Value % of Net Assets Applicable to Common StockControl Investments Aerospace & Defense $54,797 $— $— $— $7,225 $62,022 1.6 % Commercial Services & Supplies 76,017 — — 7,200 280 83,497 2.1 % Construction & Engineering 56,753 — — — 84,926 141,679 3.6 % Consumer Finance 454,041 — — — 268,049 722,090 18.2 % Diversified Consumer Services — — — — 3,833 3,833 0.1 % Energy Equipment & Services 81,566 — — — 37,697 119,263 3.0 %Equity Real Estate Investment Trusts (REITs)651,586 — — — 761,144 1,412,730 35.7 % Health Care Providers & Services 278,429 — — — 129,105 407,534 10.3 % Machinery 33,622 — — — 22,496 56,118 1.4 % Media 29,723 — — — 84,971 114,694 2.9 % Online Lending 25,058 — — — — 25,058 0.6 % Personal Products 65,336 — — — — 65,336 1.6 % Trading Companies & Distributors 32,708 — — — 3,406 36,114 0.9 %Structured Finance (A)194,510 — — — — 194,510 4.9 %Total Control Investments$2,034,146 $— $— $7,200 $1,403,132 $3,444,478 86.9 %Fair Value % of Net Assets51.3 %— %— %0.2 %35.4 %86.9 %Affiliate InvestmentsCommercial Services & Supplies$— $— $— $— $9,755 $9,755 0.2 %Diversified Consumer Services69,029 151,818 — — 66,904 287,751 7.3 %Textiles, Apparel & Luxury Goods— — — — 19,769 19,769 0.5 %Total Affiliate Investments$69,029 $151,818 $— $— $96,428 $317,275 8.0 %Fair Value % of Net Assets1.7 %3.8 %— %— %2.5 %8.0 %Non-Control/Non-Affiliate InvestmentsAir Freight & Logistics$92,978 $95,000 $— $— $— $187,978 4.7 %Auto Components22,251 100,510 — — — 122,761 3.1 %Building Products— 34,669 — — — 34,669 0.9 %Capital Markets— 41,640 — — — 41,640 1.1 %Commercial Services & Supplies69,021 181,895 — — 10,145 261,061 6.6 %Communications Equipment8,743 47,864 — — — 56,607 1.4 %Consumer Finance26,681 — — — — 26,681 0.7 %Distributors160,832 6,076 — — 2,012 168,920 4.2 %Diversified Consumer Services— 19,717 — — — 19,717 0.5 %Diversified Financial Services36,816 — — — — 36,816 0.9 %Diversified Telecommunication Services43,854 119,457 — — — 163,311 4.1 %Food & Staples Retailing27,146 — — — — 27,146 0.7 %Food Products— 125,700 — — — 125,700 3.2 %Health Care Equipment & Supplies— 6,894 — — — 6,894 0.2 %Health Care Providers & Services179,381 157,370 — — 1,542 338,293 8.4 %Health Care Technology128,927 — — — — 128,927 3.3 %Hotels, Restaurants & Leisure22,234 — — — — 22,234 0.6 % Industry1st Lien
Term Loan2nd Lien
Term LoanSubordinated Structured NotesUnsecured Debt Equity (B) Fair Value TotalFair Value % of Net Assets Applicable to Common StockHousehold Durables96,485 26,364 — — — 122,849 3.1 %Household Products20,874 — — — — 20,874 0.5 %Interactive Media & Services226,054 — — — — 226,054 5.7 %Internet & Direct Marketing Retail16,946 — — — — 16,946 0.4 %IT Services210,459 138,251 — — — 348,710 8.8 %Leisure Products67,534 — — — — 67,534 1.7 %Machinery56,713 9,749 — — — 66,462 1.7 %Media50,874 — — — 87 50,961 1.3 %Pharmaceuticals25,829 — — — — 25,829 0.7 %Professional Services66,108 119,563 — — — 185,671 4.7 %Software— 50,013 — — — 50,013 1.3 %Textiles, Apparel & Luxury Goods165,628 8,734 — — — 174,362 4.4 %Structured Finance (A)— — 695,292 — — 695,292 17.5 %Total Non-Control/Non-Affiliate$1,822,368 $1,289,466 $695,292 $— $13,786 $3,820,912 96.4 %Fair Value % of Net Assets46.0 %32.6 %17.5 %— %0.3 %96.4 %Total Portfolio$3,925,543 $1,441,284 $695,292 $7,200 $1,513,346 $7,582,665 191.3 %Fair Value % of Net Assets99.0 %36.4 %17.5 %0.2 %38.2 %191.3 % (A) Our SSN investments do not have industry concentrations and as such have been separated in the tables above. (B) Equity, unless specifically stated otherwise, includes our investments in preferred stock, common stock, membership interests, net profits interests, net operating income interests, net revenue interests, overriding royalty interests, escrows receivable, and warrants.

[2] The terms “Prospect,” “the Company,” “we,” “us” and “our” mean Prospect Capital Corporation and its subsidiaries unless the context specifically requires otherwise. The securities in which Prospect has invested were acquired in transactions that were exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”). These securities may be resold only in transactions that are exempt from registration under the Securities Act.

[3] Fair value is determined by or under the direction of our Board of Directors. Unless otherwise indicated by endnote 47 below, all of our investments are valued using significant unobservable inputs. In accordance with ASC 820, such investments are classified as Level 3 within the fair value hierarchy. See Notes 2 and 3 within the accompanying notes to consolidated financial statements for further discussion.