Business acquisition contingent consideration discounted cash flow discount rate.

No definition available.

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- Definition

Business combination consideration transferred guaranteed payment.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Business Combination, Initial Guaranteed Payment

+ References

No definition available.

+ Details

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- Definition

Business Combination, Second Guaranteed Payment

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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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

Minimum amount of other commitment maturing in the next fiscal year following the latest fiscal year for commitments not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in this taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ 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 cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

+ Details

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Period Type:	duration

- Details

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- Details

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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018
Business Acquisition [Line Items]
Commitments to purchase transportation equipment	$ 213.5		$ 213.5
WSL
Business Acquisition [Line Items]
Initial guaranteed payment		$ 19.7
Second Guaranteed Payment	20.0
Business Combination Consideration Transferred Guaranteed Payment	$ 18.7		18.7
Former Owner [Member]
Business Acquisition [Line Items]
Cash payments			$ 20.0
Former Owner [Member] \| Minimum
Business Acquisition [Line Items]
Business Acquisition Contingent Consideration Discounted Cash Flow Discount Rate			1.00%
Former Owner [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Business Acquisition Contingent Consideration Discounted Cash Flow Discount Rate			3.00%