Credit Facility Basis Point

No definition available.

Name:	fcn_CreditFacilityBasisPoint
Namespace Prefix:	fcn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility Fronting Fee Percentage

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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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- 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.

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+ 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.

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+ Details

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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

- Definition

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

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

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- Details

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- Details

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Period Type:

- Details

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Balance Type:
Period Type:

- Details

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- Details

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Debt - Narrative (Details) - USD ($)	1 Months Ended
Debt - Narrative (Details) - USD ($)	Nov. 30, 2022	Jun. 30, 2025	Dec. 31, 2024
Federal Funds
Debt Instrument [Line Items]
Credit facility basis point (as a percent)	0.50%
Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Credit facility basis point (as a percent)	1.00%
Credit Facility
Debt Instrument [Line Items]
Long-term debt, net		$ 470,000,000.0	$ 0
Current portion of long-term debt, net		$ 0
Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Senior secured revolving line of credit	$ 300,000,000
Credit Facility \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Senior secured revolving line of credit	$ 900,000,000
Credit Facility \| Line of Credit \| Minimum
Debt Instrument [Line Items]
Commitment fee (as a percent)	0.20%
Fronting fees (as a percent)	1.25%
Credit Facility \| Line of Credit \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as a percent)	1.25%
Credit Facility \| Line of Credit \| Minimum \| Base Rate
Debt Instrument [Line Items]
Basis spread (as a percent)	0.25%
Credit Facility \| Line of Credit \| Maximum
Debt Instrument [Line Items]
Commitment fee (as a percent)	0.35%
Fronting fees (as a percent)	2.00%
Credit Facility \| Line of Credit \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as a percent)	2.00%
Credit Facility \| Line of Credit \| Maximum \| Base Rate
Debt Instrument [Line Items]
Basis spread (as a percent)	1.00%