Commitments and Contingencies (Future Minimum Rental Payments Under All Non-Cancelable Operating Leases) (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Property Subject to or Available for Operating Lease [Line Items]
2019	$ 46,042
2020	39,355
2021	30,674
2022	27,458
2023	27,629
2024 and thereafter	126,229
Total minimum lease obligations	297,387
Office Space
Property Subject to or Available for Operating Lease [Line Items]
2019	4,197
2020	4,119
2021	3,298
2022	2,692
2023	961
2024 and thereafter	3,735
Total minimum lease obligations	19,002
Transportation equipment
Property Subject to or Available for Operating Lease [Line Items]
2019	27,547
2020	24,642
2021	19,536
2022	18,113
2023	17,290
2024 and thereafter	45,390
Total minimum lease obligations	152,518
Terminals and Tanks
Property Subject to or Available for Operating Lease [Line Items]
2019	14,298
2020	10,594
2021	7,840
2022	6,653
2023	9,378
2024 and thereafter	77,104
Total minimum lease obligations	$ 125,867

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
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
-Section 50
-Paragraph 2
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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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-Paragraph 2
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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 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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