Debt Instrument, Basis Spread On Variable Rate, Adjustment

No definition available.

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

- Definition

Line Of Credit Facility Fronting Fee Percentage

+ References

No definition available.

+ Details

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Balance Type:	na
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- 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_
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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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- 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 cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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- Details

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Debt - Additional Information (Details) - USD ($)		3 Months Ended	6 Months Ended
Debt - Additional Information (Details) - USD ($)	Mar. 17, 2026	Jun. 30, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 29, 2026
Debt Instrument [Line Items]
Payments of debt issuance costs		$ 4,600,000	$ 5,401,000	$ 0
Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Senior secured revolving line of credit		1,500,000,000	$ 1,500,000,000		$ 900,000,000.0
Credit Facility \| Line of Credit \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Variable rate, adjustment (as a percent)	1.00%
Credit Facility \| Line of Credit \| Federal Funds Base Rate
Debt Instrument [Line Items]
Basis spread (as a percent)			0.50%
Credit Facility \| Line of Credit \| Minimum
Debt Instrument [Line Items]
Commitment fee (as a percent)			0.125%
Fronting fees (as a percent)			1.00%
Credit Facility \| Line of Credit \| Minimum \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread (as a percent)			1.00%
Credit Facility \| Line of Credit \| Minimum \| Base Rate
Debt Instrument [Line Items]
Basis spread (as a percent)			0.00%
Credit Facility \| Line of Credit \| Maximum
Debt Instrument [Line Items]
Commitment fee (as a percent)			0.275%
Fronting fees (as a percent)			1.625%
Credit Facility \| Line of Credit \| Maximum \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread (as a percent)			1.625%
Credit Facility \| Line of Credit \| Maximum \| Base Rate
Debt Instrument [Line Items]
Basis spread (as a percent)			0.625%
Incremental Facility \| Line of Credit
Debt Instrument [Line Items]
Senior secured revolving line of credit	$ 300,000,000.0	$ 500,000,000.0	$ 500,000,000.0