Intangible Assets, Goodwill and Other Assets (Schedule of Estimated Amortization Expense) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Finite-Lived Intangible Assets [Line Items]
2020	$ 15,312
2021	10,526
2022	10,366
2023	9,976
2024	9,775
Other
Finite-Lived Intangible Assets [Line Items]
2020	2,453
2021	2,168
2022	2,010
2023	1,621
2024	1,421
Marine transportation \| Contract intangible
Finite-Lived Intangible Assets [Line Items]
2020	4,538
2021	37
2022	35
2023	34
2024	33
Offshore pipeline transportation \| Contract intangible
Finite-Lived Intangible Assets [Line Items]
2020	8,321
2021	8,321
2022	8,321
2023	8,321
2024	$ 8,321

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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