Long-term Debt - Components (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, gross	$ 454,376	$ 367,351
Less: Debt issuance costs	(322)	(357)
Less: Current maturities of long-term debt	(113,952)	(83,584)
Long-term debt, excluding current maturities	340,102	283,410
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	91,966	23,900
Revenue Equipment Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 338,923	$ 310,420
Weighted average interest rate	3.90%	3.70%
Collateral	$ 354,600	$ 316,900
Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	23,487	24,587
Collateral	$ 32,400	$ 33,000
Mortgages \| Minimum
Debt Instrument [Line Items]
Interest rate	4.17%	4.17%
Mortgages \| Maximum
Debt Instrument [Line Items]
Interest rate	6.99%	6.99%
Other Debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 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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- Definition

Weighted average interest rate of debt outstanding.

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- Definition

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, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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