Debt secured with a cross default feature.

No definition available.

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- Definition

Represents the fixed charge coverage requirement.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The availability of line of credit facility as percentage of the revolver commitment.

+ References

No definition available.

+ Details

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- Definition

Represents percentage of aggregate commitments as borrowing capacity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The maximum commitment value for a line of credit facility.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility's maximum increase in borrowing capacity as long as no event of default exists.

+ References

No definition available.

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- Definition

The revolver commitment amount.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The percent of the lenders' aggregate commitments under the credit facility.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

Percent of appraised fair market value of eligible real estate used in the calculation of borrowing base.

+ References

No definition available.

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Period Type:	duration

- Definition

The percent of appraised net orderly liquidation value of eligible revenue equipment used in the calculation of borrowing base.

+ References

No definition available.

+ Details

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- Definition

Percent of the eligible accounts receivable used in the calculation of borrowing base.

+ References

No definition available.

+ Details

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- Definition

Percent of net book value of eligible revenue equipment used in the calculation of borrowing base.

+ References

No definition available.

+ Details

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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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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of assets pledged to secure a debt instrument.

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Balance Type:	debit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

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

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of cash inflow (outflow) from (to) the discontinued operation after the disposal transaction.

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

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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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

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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

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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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Data Type:	dtr-types:percentItemType
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Note 8 - Debt (Details Textual) - USD ($) $ in Thousands			3 Months Ended		12 Months Ended
Note 8 - Debt (Details Textual) - USD ($) $ in Thousands	Oct. 23, 2020	Sep. 23, 2020	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Sep. 23, 2021	Aug. 31, 2015
Letters of Credit Outstanding, Amount					$ 26,400	$ 29,700
Repayments of Lines of Credit					$ 695,513	1,326,678
Transport Financial Services [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Discontinued Operation, Amount of Continuing Cash Flows after Disposal				$ (35,600)
Interest Rate Swap [Member]
Derivative, Fixed Interest Rate								4.20%
Variable Rate Note [Member]
Debt Instrument, Face Amount								$ 28,000
Lenders [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Percent of Eligible Accounts Receivable	87.50%				85.00%
Percent of Appraised Net Orderly Liquidation, Value of Eligible Revenue Equipment	85.00%
Percent of Net Book Value of Eligible Revenue Equipment	100.00%				95.00%
Line of Credit Facility, Availability as Percentage of Revolver Commitment	40.90%				35.00%
Line of Credit Facility, Revolver Commitment, Amount	$ 45,000
Line of Credit Facility, Maximum Commitment Value	$ 10,400
Percent of Appraised Fair Market Value of Eligible Real Estate	80.00%				75.00%
Long-term Line of Credit, Total					$ 0
Letters of Credit Outstanding, Amount					26,400
Line of Credit Facility, Remaining Borrowing Capacity					83,600
Fixed Charge Coverage Requirement					0	$ 0
Debt, Secured with a Cross Default Feature					$ 4,500
Lenders [Member] \| Federal Funds Rate [Member] \| Base Rate Loans [Member]
Debt Instrument, Basis Spread on Variable Rate					0.50%
Lenders [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Base Rate Loans [Member]
Debt Instrument, Basis Spread on Variable Rate					1.00%
Lenders [Member] \| Applicable Margin [Member] \| Base Rate Loans [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	0.25%				0.50%
Lenders [Member] \| Applicable Margin [Member] \| Base Rate Loans [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	0.75%				1.00%
Lenders [Member] \| Applicable Margin [Member] \| LIBOR Loans [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	1.25%				1.50%
Lenders [Member] \| Applicable Margin [Member] \| LIBOR Loans [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	1.75%				2.00%
Lenders [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 110,000				$ 95,000
Line of Credit Facility, Maximum Increase in Borrowing Capacity	50,000
Lenders [Member] \| Letter of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity	105,000				95,000
Line of Credit Facility, Borrowing Capacity, Percentage of Aggregate Commitments	$ 10,000
Lenders [Member] \| Swing Line Sub Facility [Member]
Percent of Aggregate Commitments under Credit Facility	10.00%
TBK Bank [Member] \| Draw Note [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 45,000
Debt Instrument, Collateral Amount							$ 60,000
Repayments of Lines of Credit			$ 31,000
Long-term Debt, Total					$ 0
TBK Bank [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Draw Note [Member]
Debt Instrument, Basis Spread on Variable Rate		1.50%
TBK Bank [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Draw Note [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate		0.25%