Leases, Schedule of Future Minimum Lease Payments Under Operating Leases (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Future Minimum Lease Payments under Operating Leases [Abstract]
2019	$ 97,091
2020	30,062
2021	21,818
2022	20,263
2023	17,429
Thereafter	91,939
Future minimum lease payments under operating leases	278,602
Marine Equipment [Member] \| Barges [Member]
Future Minimum Lease Payments under Operating Leases [Abstract]
2019	6,808
2020	5,400
2021	4,128
2022	4,138
2023	3,030
Thereafter	7,098
Future minimum lease payments under operating leases	30,602
Marine Equipment [Member] \| Towing Vessels [Member]
Future Minimum Lease Payments under Operating Leases [Abstract]
2019	70,759
2020	7,746
2021	2,578
2022	2,578
2023	2,578
Thereafter	9,023
Future minimum lease payments under operating leases	95,262
Land Buildings and Equipment [Member]
Future Minimum Lease Payments under Operating Leases [Abstract]
2019	19,524
2020	16,916
2021	15,112
2022	13,547
2023	11,821
Thereafter	75,818
Future minimum lease payments under operating leases	$ 152,738

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after 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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