Organization, Description of Business and Basis of Presentation (Narrative) (Details) $ in Thousands, bbl in Millions	3 Months Ended
	Mar. 31, 2018 USD ($) Terminal bbl mi	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Organization and Description of Business [Line Items]
Operating	$ 143,296	$ 131,592
General and administrative	46,556	40,281
Other expense	8,724	$ 1,170
Long-term pension and benefits	131,248		$ 111,305
Accumulated other comprehensive loss	$ 132,299		$ 137,578
Refined Products Segment [Member]
Organization and Description of Business [Line Items]
Number of Pipeline Terminals | Terminal	53
Number of Independent Terminals | Terminal	26
Refined Products Segment [Member] | Refined Products Transportation Services [Member]
Organization and Description of Business [Line Items]
Pipeline Length | mi	9,700
Refined Products Segment [Member] | Ammonia Transportation Services [Member]
Organization and Description of Business [Line Items]
Pipeline Length | mi	1,100
Crude Oil Pipeline and Terminals Segment [Member]
Organization and Description of Business [Line Items]
Pipeline Length | mi	2,200
Storage Capacity | bbl	28
Contracted Storage | bbl	17
Marine Storage Segment [Member]
Organization and Description of Business [Line Items]
Number of Independent Terminals | Terminal	5
Storage Capacity | bbl	26
Error in Actuarial Assumptions [Member]
Organization and Description of Business [Line Items]
Net periodic benefit cost (credit)	$ 16,000
Operating	5,700
General and administrative	3,400
Other expense	6,900
Long-term pension and benefits	18,800
Accumulated other comprehensive loss	$ 2,800