Long-term Debt - Components (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt, gross	$ 386,444	$ 384,823
Less: Debt issuance costs	(325)	(1,223)
Less: Current maturities of long-term debt	(107,165)	(75,596)
Long-term debt, excluding current maturities	278,954	$ 308,004
Facility interest rate		4.30%
Term Facility [Member]
Debt Instrument [Line Items]
Long-term debt, gross		$ 150,000
Revenue equipment notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 344,281	$ 208,252
Weighted average interest rate	4.20%	4.70%
Collateral	$ 344,500	$ 220,400
Mortgages [Member]
Debt Instrument [Line Items]
Long-term debt, gross	26,312	17,776
Collateral	$ 32,200	$ 20,200
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	$ 15,851	$ 8,795

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

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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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The effective interest rate at the end of the reporting period.

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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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