Refers to the number of maritime (seagoing) vessels acquired.

No definition available.

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- Definition

Refers to the number of states made available through the distribution agreement.

+ References

No definition available.

+ Details

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- Definition

The average age of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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- Definition

Refers to the carrying capacity of tank barges as measured in number of barrels.

+ References

No definition available.

+ Details

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-SubTopic 10
-Section 45
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Balance Type:	credit
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- Definition

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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- Details

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- Details

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- Details

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Acquisitions, 2016 (Details) $ in Thousands								12 Months Ended
Acquisitions, 2016 (Details) $ in Thousands	Dec. 28, 2018 USD ($) TankBarge	Dec. 14, 2018 USD ($) TankBarge bbl	Nov. 30, 2018 USD ($) Towboat	Oct. 11, 2016 USD ($) State	Jun. 30, 2016 USD ($) TankBarge bbl	Jun. 02, 2016 USD ($) Tugboat	Apr. 15, 2016 USD ($) TankBarge Towboat bbl	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Acquisitions [Abstract]
Purchase price								$ 301,861	$ 177,222	$ 231,066
Inland Tank Barges [Member]
Acquisitions [Abstract]
Purchase price	$ 3,120	$ 28,500
Number of maritime vessels acquired \| TankBarge	3	27
Tank barge barrel capacity (in barrels) \| bbl		306,000
Average age of property		8 years
Inland Towboats [Member]
Acquisitions [Abstract]
Purchase price			$ 3,050
Number of maritime vessels acquired \| Towboat			1
Valley Power Systems Northwest, Inc. [Member]
Acquisitions [Abstract]
Purchase price				$ 11,440
Goodwill acquired				8,330
Intangible assets acquired				$ 2,070
Weighted average amortization period of intangibles				15 years
Number of western states included in distributor agreement \| State				9
TD Equipment Finance, Inc. [Member] \| Coastal Tank Barge [Member]
Acquisitions [Abstract]
Purchase price					$ 13,682
Number of maritime vessels acquired \| TankBarge					1
Tank barge barrel capacity (in barrels) \| bbl					80,000
Crosby Marine Transportation LLC [Member] \| Coastal Tugboats [Member]
Acquisitions [Abstract]
Purchase price						$ 26,450
Number of maritime vessels acquired \| Tugboat						4
Average age of property						13 years
SEACOR Holdings Inc. [Member]
Acquisitions [Abstract]
Purchase price							$ 89,181
Cash paid for acquisition							85,500
Ownership transferred, value							3,681
Goodwill acquired							985
Intangible assets acquired							$ 0
SEACOR Holdings Inc. [Member] \| Inland Tank Barges [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired \| TankBarge							27
Tank barge barrel capacity (in barrels) \| bbl							30,000
Average age of property							10 years
SEACOR Holdings Inc. [Member] \| Inland Towboats [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired \| Towboat							14