Borrowing Base

No definition available.

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- Definition

Debt Covenant, Commitment

+ References

No definition available.

+ Details

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Namespace Prefix:	cmls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Covenant, Outstanding Amount to Trigger Conditional Maturity Date

+ References

No definition available.

+ Details

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

- Definition

Debt Covenant, Total Commitments

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- 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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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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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+ Details

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

- Definition

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

+ References

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- 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
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-SubTopic 10
-Section S99
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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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Balance Type:	na
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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Long-Term Debt - 2020 Revolving Credit Agreement (Details) - USD ($)	May 17, 2021	Mar. 06, 2020	Dec. 31, 2022	Jun. 03, 2022
Debt Instrument [Line Items]
Debt covenant, outstanding amount to trigger conditional maturity date				$ 35,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 100,000,000
Borrowing base		85.00%
Unused capacity, commitment fee rate		0.25%
Debt covenant, total commitments		12.50%
Debt covenant, commitment		$ 10,000,000
Fixed charge coverage ratio		1.0
Debt instrument, unamortized discount			$ 600,000
Debt issuance cost (premium)			400,000
Repayments of debt	$ 60,000,000
Letters of credit outstanding amount			$ 4,500,000
Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 10,000,000
Swing Line Loans
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 10,000,000
Alternative Base Rate \| Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Secured Overnight Financing Rate (SOFR) \| Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate		0.10%