v3.23.3

Borrowings - Narrative (Details) - USD ($) |  |  |  | 8 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 15, 2023 | May 18, 2021 | Feb. 25, 2020 | Sep. 30, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Borrowings outstanding |  |  |  | $ 710,000,000 | $ 710,000,000 | $ 700,000,000 |
Interest expense |  |  |  |  | 111,642,000 | 46,929,000 | $ 30,518,000
Fair Value |  |  |  | 1,588,201,000 | $ 1,588,201,000 | $ 1,277,105,000 |
Interest rate swap |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 2.70% |
Floating interest rate |  |  |  |  |  | 1.658% |
Notional amount |  |  |  |  |  | $ 350,000,000 |
Interest rate swap | Designated as Hedging Instrument |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Interest rate |  | 2.70% |  |  |  |  |
Notional amount |  | $ 350,000,000 |  |  |  |  |
Secured Overnight Financing Rate |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Interest rate |  |  |  |  | 2.00% |  |
Secured Overnight Financing Rate | Minimum |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread, variable rate |  |  |  |  | 0.11448% |  |
Secured Overnight Financing Rate | Maximum |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread, variable rate |  |  |  |  | 0.26161% |  |
London Interbank Offered Rate (LIBOR) | Interest rate swap | Designated as Hedging Instrument |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Floating interest rate |  | 1.658% |  |  |  |  |
Base Rate |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Interest rate |  |  |  |  | 1.00% |  |
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Interest rate swap | Designated as Hedging Instrument |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Floating interest rate |  | 0.26161% |  |  |  |  |
Citibank Facility |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Interest expense |  |  |  |  | $ 600,000 |  |
2025 Notes |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Principal amount |  |  | $ 300,000,000 | 300,000,000.0 | 300,000,000.0 | 300,000,000.0 |
Net proceeds |  |  | 293,800,000 |  |  |  |
Unaccreted discount |  |  | 2,500,000 | $ 700,000 | $ 700,000 | 1,200,000 |
Underwriting commissions |  |  | 3,000,000 |  |  |  |
Offering costs |  |  | $ 700,000 |  |  |  |
Interest rate, percentage |  |  | 3.50% | 3.50% | 3.50% |  |
Redemption price |  |  | 100.00% |  |  |  |
2027 Notes |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Principal amount |  | $ 350,000,000 |  | $ 350,000,000.0 | $ 350,000,000.0 | 350,000,000.0 |
Net proceeds |  | 344,800,000 |  |  |  |  |
Unaccreted discount |  | 1,000,000 |  | $ 600,000 | $ 600,000 | 700,000 |
Underwriting commissions |  | 3,500,000 |  |  |  |  |
Offering costs |  | $ 700,000 |  |  |  |  |
Interest rate, percentage |  | 2.70% |  | 2.70% | 2.70% |  |
Redemption price |  | 100.00% |  |  |  |  |
2029 Notes |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Principal amount | $ 300,000,000 |  |  | $ 300,000,000.0 | $ 300,000,000.0 |  |
Net proceeds | 292,900,000 |  |  |  |  |  |
Unaccreted discount | 3,500,000 |  |  | $ 3,400,000 | $ 3,400,000 |  |
Underwriting commissions | 3,000,000 |  |  |  |  |  |
Offering costs | $ 600,000 |  |  |  |  |  |
Interest rate, percentage | 7.10% |  |  | 7.10% | 7.10% |  |
Redemption price | 100.00% |  |  |  |  |  |
2029 Notes | Interest rate swap | Designated as Hedging Instrument |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Interest rate |  | 7.10% |  |  |  |  |
Notional amount |  | $ 300,000,000 |  |  |  |  |
2029 Notes | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Interest rate swap | Designated as Hedging Instrument |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Floating interest rate |  | 3.1255% |  |  |  |  |
Line of Credit | Revolving Credit Facility | Syndicated Facility |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Borrowing capacity |  |  |  | $ 1,218,000,000 | $ 1,218,000,000 |  |
Accordion feature, increase limit |  |  |  | 1,250,000,000 | 1,250,000,000 |  |
Borrowing capacity subject to expiration |  |  |  | $ 1,035,000,000.000 | $ 1,035,000,000.000 |  |
Debt instrument, covenant, total assets to total indebtedness, ratio, minimum threshold |  |  |  | 1.50 | 1.50 |  |
Debt instrument, covenant, consolidated EBITDA to consolidated interest expense, ratio, minimum threshold |  |  |  | 2.25 | 2.25 |  |
Borrowings outstanding |  |  |  | $ 430,000,000 | $ 430,000,000 | 540,000,000 |
Fair value |  |  |  | $ 430,000,000 | $ 430,000,000 | $ 540,000,000 |
Weighted average interest rate |  |  |  | 6.792% | 6.792% | 2.876% | 2.197%
Interest expense inclusive of fees |  |  |  |  | $ 50,000,000 | $ 19,500,000 | $ 13,800,000
Line of Credit | Revolving Credit Facility | Citibank Facility |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Borrowings outstanding |  |  |  |  |  | 160,000,000 |
Fair value |  |  |  |  |  | $ 160,000,000 |
Weighted average interest rate |  |  |  | 6.781% | 6.781% | 3.179% | 2.086%
Interest expense inclusive of fees |  |  |  |  | $ 8,000,000 | $ 5,800,000 | $ 1,900,000
Line of Credit | Revolving Credit Facility | OSI2 Citibank Facility |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Borrowing capacity |  |  |  | $ 400,000,000 | 400,000,000 |  |
Borrowings outstanding |  |  |  | $ 280,000,000 | $ 280,000,000 |  |
Weighted average interest rate |  |  |  | 7.666% | 7.666% |  |
Interest expense inclusive of fees |  |  |  | $ 14,600,000 |  |  |
Unused capacity, commitment fee |  |  |  |  | 0.50% |  |
Commitment fee, unused capacity threshold percentage |  |  |  | 30.00% | 30.00% |  |
Fair Value |  |  |  | $ 280,000,000 | $ 280,000,000 |  |
Line of Credit | Revolving Credit Facility | OSI2 Citibank Facility | Secured Overnight Financing Rate | After Reinvestment Period |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread, variable rate |  |  |  |  | 4.00% |  |
Line of Credit | Revolving Credit Facility | OSI2 Citibank Facility | Secured Overnight Financing Rate | Minimum |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread, variable rate |  |  |  |  | 2.50% |  |
Line of Credit | Revolving Credit Facility | OSI2 Citibank Facility, Syndicated Loans | Secured Overnight Financing Rate |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread, variable rate |  |  |  |  | 2.00% |  |
Line of Credit | Revolving Credit Facility | OSI2 Citibank Facility, All Other Loans | Secured Overnight Financing Rate |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread, variable rate |  |  |  |  | 2.75% |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482900/835-30-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69B -Publisher FASB -URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69C -Publisher FASB -URI https://asc.fasb.org//1943274/2147481568/470-20-55-69C Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482925/835-30-45-2 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482949/835-30-55-8 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Amount, after accumulated amortization, of debt discount. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org//1943274/2147482925/835-30-45-1A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482949/835-30-55-8 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D + Details
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- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
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- Definition Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482925/835-30-45-3 + Details
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- Definition The percentage points added to the reference rate to compute the variable rate on the interest rate derivative. + References No definition available. + Details
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- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A + Details
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- Definition Interest and debt related expenses associated with nonoperating financing activities of the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 20 -Topic 835 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483013/835-20-50-1 + Details
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480167/946-830-55-10 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483581/946-220-45-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(3)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-22 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482925/835-30-45-3 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (210.5-03(11)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483013/835-20-50-1 + Details
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- Definition Amount of fees and commissions from banking, advisory, brokerage, and securities underwriting activities. Activities include, but are not limited to, underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, sale and servicing of mutual funds, and other related consulting fees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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- Definition Fair value of the amount outstanding under the credit facility. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-10 + Details
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- Definition The effective interest rate during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(f)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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- Definition The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 14 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-14 + Details
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