Fixed Assets and Mineral Leaseholds (Schedule of Fixed Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fixed assets, at cost	$ 5,522,292	$ 4,763,396
Less: Accumulated depreciation	(681,900)	(548,532)
Net fixed assets	4,840,392	4,214,864
Crude oil pipelines and natural gas pipelines and related assets
Fixed assets, at cost	3,004,618	2,901,202
Onshore facilities, machinery, and equipment
Fixed assets, at cost	757,874	427,658
Onshore facilities, machinery, and equipment \| Alkali Business
Fixed assets, at cost	617,878	0
Transportation equipment
Fixed assets, at cost	17,995	17,543
Marine vessels
Fixed assets, at cost	898,582	863,199
Land, buildings and improvements
Fixed assets, at cost	103,774	55,712
Office equipment, furniture and fixtures
Fixed assets, at cost	9,681	9,654
Construction in progress
Fixed assets, at cost	58,069	440,225
Other
Fixed assets, at cost	$ 53,821	$ 48,203

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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