Long-term Debt - Credit Facilities (Details) - USD ($) $ in Millions	Jan. 28, 2020	Mar. 31, 2021
Debt Instrument [Line Items]
Letters of credit outstanding		$ 28.1
Borrowing base limit	$ 250.0
Limitation on billed accounts receivable, as a percent	87.50%
Limitation on unbilled accounts receivable, as a percent	85.00%
Limitation on net book value of equipment, as a percent	85.00%
Limitation on fair market value of real estate, as a percent	80.00%
Limitation alternative to real estate	$ 25.0
Fixed charge coverage ratio, as a percent	100.00%
Covenant testing trigger, as a percent	10.00%
Covenant testing trigger, amount	$ 20.0
Base Rate Loans [Member]
Debt Instrument [Line Items]
Quarterly adjustment to rate, as a percent	0.50%
Base Rate Loans [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Quarterly adjustment to rate, as a percent	0.25%
Base Rate Loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Quarterly adjustment to rate, as a percent	0.75%
Base Rate Loans [Member] \| Federal Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate, as a percent	0.50%
Base Rate Loans [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate, as a percent	1.00%
Eurodollar Rate Loans [Member]
Debt Instrument [Line Items]
Basis spread on variable rate, as a percent	1.50%
Eurodollar Rate Loans [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Quarterly adjustment to rate, as a percent	1.25%
Eurodollar Rate Loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Quarterly adjustment to rate, as a percent	1.75%
Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	5 years
Letters of credit outstanding		28.1
Amount available to borrow		162.1
Amount outstanding		$ 13.2
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity	$ 250.0
Commitment fee, as a percent	0.25%
Borrowing base limit	$ 250.0
Letter of Credit [Member]
Debt Instrument [Line Items]
Borrowing capacity	75.0
Swingline Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity	$ 25.0

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- 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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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- 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

+ Details

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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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The maximum amount, as an alternative to a percentage of fair market value of real estate, that may contribute to the borrowing base for the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The maximum percent of billed accounts receivable that may contribute to the borrowing base for the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The maximum percent of net orderly liquidation value applied to the net book value of eligible revenue equipment, that may contribute to the borrowing base for the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The maximum percent of fair market value of eligible real estate that may contribute to the borrowing base for the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The maximum percent of unbilled accounts receivable that may contribute to the borrowing base for the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The maximum borrowing base to which the debt instrument borrowings are limited.

+ References

No definition available.

+ Details

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- Definition

The minimum fixed charge coverage ratio, per the debt instrument covenant.

+ References

No definition available.

+ Details

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- Definition

The financial covenant is tested only in the event excess availability under the Credit Facility is less than the greater of (A) 10.0% of the lesser of the borrowing base or revolving credit facility or (B) this amount.

+ References

No definition available.

+ Details

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- Definition

The financial covenant is tested only in the event excess availability under the Credit Facility is less than the greater of this percentage of the lesser of the borrowing base or revolving credit facility or (B) $20.0 million.

+ References

No definition available.

+ Details

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- Definition

Percentage points added as a quarterly adjustment to the basis spread on the variable rate.

+ References

No definition available.

+ Details

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