Debt instrument maturity year.

No definition available.

Name:	tcpc_DebtInstrumentMaturityYear
Namespace Prefix:	tcpc_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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+ Details

Name:	us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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.

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+ Details

Name:	us-gaap_LineOfCredit
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_LineOfCreditFacilityLineItems
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

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=tcpc_OperatingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=tcpc_FundingFacilityIIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=tcpc_SBADebenturesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=tcpc_TwoThousandTwentyFourNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=tcpc_TwoThousandTwentySixNotesMember
Namespace Prefix:
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Balance Type:
Period Type:

Debt - Schedule of Total Debt Outstanding and Available (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Feb. 28, 2023	Jun. 22, 2021
Line Of Credit Facility [Line Items]
Carrying Value	$ 1,027,257,436	$ 949,062,241
Available	207,966,879	286,110,020
Total Capacity	1,235,224,315	1,235,172,261
Unamortized issuance costs	(4,636,951)	(5,056,427)
Debt, net of unamortized issuance costs	$ 1,022,620,485	$ 944,005,814
SOFR
Line Of Credit Facility [Line Items]
Rate	0.15%
Operating Facility
Line Of Credit Facility [Line Items]
Total Capacity	$ 300,000,000.0
Operating Facility \| LIBOR
Line Of Credit Facility [Line Items]
Maturity	2026	2026
Rate	1.75%	1.75%
Carrying Value	$ 202,033,121	$ 123,889,980
Available	97,966,879	176,110,020
Total Capacity	300,000,000	$ 300,000,000
Operating Facility \| LIBOR \| Minimum
Line Of Credit Facility [Line Items]
Rate				1.75%
Operating Facility \| LIBOR \| Maximum
Line Of Credit Facility [Line Items]
Rate				2.00%
Funding Facility II
Line Of Credit Facility [Line Items]
Rate			2.00%
Total Capacity	$ 200,000,000.0
Funding Facility II \| LIBOR
Line Of Credit Facility [Line Items]
Maturity		2025
Rate	2.00%	2.00%
Carrying Value		$ 100,000,000
Available		100,000,000
Total Capacity		$ 200,000,000
Funding Facility II \| SOFR
Line Of Credit Facility [Line Items]
Maturity	2025
Rate	2.00%		0.15%
Carrying Value	$ 100,000,000
Available	100,000,000
Total Capacity	$ 200,000,000
SBA Debentures
Line Of Credit Facility [Line Items]
Rate	2.52%	2.52%
Carrying Value	$ 150,000,000	$ 150,000,000
Available	10,000,000	10,000,000
Total Capacity	$ 160,000,000	$ 160,000,000
SBA Debentures \| Minimum
Line Of Credit Facility [Line Items]
Maturity	2024	2024
SBA Debentures \| Maximum
Line Of Credit Facility [Line Items]
Maturity	2031	2031
2024 Notes
Line Of Credit Facility [Line Items]
Maturity	2024	2024
Rate	3.90%	3.90%
Carrying Value	$ 249,144,733	$ 248,997,527
Available	0	0
Total Capacity	$ 249,144,733	$ 248,997,527
2026 Notes
Line Of Credit Facility [Line Items]
Maturity	2026	2026
Rate	2.85%	2.85%
Carrying Value	$ 326,079,582	$ 326,174,734
Available	0	0
Total Capacity	$ 326,079,582	$ 326,174,734