Long-term Debt - Components (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, gross	$ 413,753	$ 367,351
Less: Debt issuance costs	(333)	(357)
Less: Current maturities of long-term debt	(111,828)	(83,584)
Long-term debt, excluding current maturities	301,592	283,410
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, gross	69,200	23,900
Revenue equipment notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 319,203	310,420
Weighted average interest rate	3.60%
Collateral	$ 333,000	316,900
Mortgages [Member]
Debt Instrument [Line Items]
Long-term debt, gross	23,859	24,587
Collateral	$ 32,500	$ 33,000
Mortgages [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate	4.17%	4.17%
Mortgages [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate	6.99%	6.99%
Other Debt [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,491	$ 8,444

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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Weighted average interest rate of debt outstanding.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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