Debt Instrument, Extension Option, Term

No definition available.

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Namespace Prefix:	arcc_
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Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=arcc_BNPFundingFacilityMember
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_VariableRateAxis=arcc_SecuredOvernightFinancingRateSOFRMember
Namespace Prefix:
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- Details

Name:	us-gaap_VariableRateAxis=arcc_BaseRateDuringReinvestmentPeriodMember
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- Details

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DEBT - BNP Funding Facility Narrative (Details) - USD ($)			3 Months Ended
	Mar. 31, 2023	Jan. 08, 2023	Mar. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Principal amount of debt outstanding	$ 11,196,000,000		$ 11,196,000,000	$ 11,196,000,000	$ 12,245,000,000
BNP Funding Facility \| Minimum
Debt Instrument [Line Items]
Percentage of unused portion of line of credit commitment				0.00%
BNP Funding Facility \| Maximum
Debt Instrument [Line Items]
Percentage of unused portion of line of credit commitment				1.25%
BNP Funding Facility \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity of line of credit	500,000,000		500,000,000	$ 500,000,000
Term of debt maturity extension option				1 year
Principal amount of debt outstanding	$ 320,000,000		$ 320,000,000	$ 320,000,000	$ 245,000,000
BNP Funding Facility \| Line of Credit \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate spread	2.30%
BNP Funding Facility \| Line of Credit \| Base Rate, During Reinvestment Period
Debt Instrument [Line Items]
Interest rate spread		1.80%	2.30%
BNP Funding Facility \| Line of Credit \| Base Rate, After Reinvestment Period
Debt Instrument [Line Items]
Interest rate spread		2.30%	2.80%