Debt Instrument, Interest Free Period

No definition available.

Name:	ctos_DebtInstrumentInterestFreePeriod
Namespace Prefix:	ctos_
Data Type:	xbrli:durationItemType
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

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

Period between issuance and maturity of debt instrument, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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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.

+ References

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- Details

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- Details

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- Details

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- Details

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Floor Plan Financing - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Aug. 25, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Floor Plan Financing Arrangements
Debt Instrument [Line Items]
Interest expense		$ 10.8	$ 13.8	$ 32.5	$ 40.8
Daimler Truck Financial \| Line of Credit
Debt Instrument [Line Items]
Debt instrument, interest free period (up to)				150 days
Maximum borrowing capacity		175.0		$ 175.0
PACCAR Financial Corp \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity		225.0		$ 225.0
PACCAR Financial Corp \| Line of Credit \| Prime Rate
Debt Instrument [Line Items]
Debt instrument, basis spread				(0.71%)
Ford Motor Credit Company, LLC \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity		42.0		$ 42.0
PNC Equipment Finance, LLC \| Line of Credit \| Revolving Credit Facility \| PNC Equipment Finance, LLC
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 475.0		$ 475.0
Debt instrument, term	1 year
PNC Equipment Finance, LLC \| Line of Credit \| Secured Overnight Financing Rate (SOFR) \| Revolving Credit Facility \| PNC Equipment Finance, LLC
Debt Instrument [Line Items]
Debt instrument, basis spread				2.75%