Segments (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2015 USD ($) item	Jun. 30, 2014 USD ($)	Mar. 31, 2015 USD ($)
Segment information
Revenue	$ 3,538,469	$ 3,648,614
Depreciation and amortization	59,831	39,375
Operating income (loss)	(14,729)	(20,555)
Additions to property, plant and equipment	164,065	54,867
Total assets	6,642,651		$ 6,547,501
Long-lived assets, net	4,446,716		4,308,493
Crude oil logistics
Segment information
Depreciation and amortization	10,002	9,731
Operating income (loss)	11,960	1,463
Additions to property, plant and equipment	62,639	41,949
Total assets	2,269,187		2,337,188
Long-lived assets, net	1,379,921		1,327,538
Water solutions
Segment information
Depreciation and amortization	20,846	17,092
Operating income (loss)	(3,072)	(907)
Additions to property, plant and equipment	60,489	7,462
Total assets	1,298,697		1,185,929
Long-lived assets, net	1,204,133		1,119,794
Liquids
Segment information
Depreciation and amortization	5,004	3,201
Operating income (loss)	(471)	(913)
Additions to property, plant and equipment	17,178	1,159
Total assets	737,114		713,547
Long-lived assets, net	$ 546,204		534,560
Retail propane
Segment information
Number of operating divisions | item	2
Depreciation and amortization	$ 8,706	7,571
Operating income (loss)	(700)	(1,586)
Additions to property, plant and equipment	6,895	2,844
Total assets	528,934		542,476
Long-lived assets, net	468,007		467,652
Refined products and renewables
Segment information
Depreciation and amortization	14,175	844
Operating income (loss)	33,020	(1,255)
Additions to property, plant and equipment	15,695
Total assets	1,671,503		1,668,836
Long-lived assets, net	800,457		808,757
Corporate and other
Segment information
Depreciation and amortization	1,098	936
Operating income (loss)	(55,466)	(17,357)
Additions to property, plant and equipment	1,169	1,453
Total assets	137,216		99,525
Long-lived assets, net	47,994		$ 50,192
Operating segment | Crude oil logistics | Crude oil
Segment information
Revenue	1,312,783	1,929,055
Operating segment | Crude oil logistics | Crude oil transportation and other
Segment information
Revenue	18,949	10,003
Operating segment | Water solutions | Water transportation
Segment information
Revenue		5,598
Operating segment | Water solutions | Service fees
Segment information
Revenue	36,738	17,701
Operating segment | Water solutions | Recovered hydrocarbons
Segment information
Revenue	15,818	24,015
Operating segment | Water solutions | Other revenues
Segment information
Revenue	1,737
Operating segment | Liquids | Propane sales
Segment information
Revenue	105,162	222,446
Operating segment | Liquids | Other product sales
Segment information
Revenue	147,589	288,359
Operating segment | Liquids | Other revenues
Segment information
Revenue	9,750	5,716
Operating segment | Retail propane | Propane sales
Segment information
Revenue	43,185	52,026
Operating segment | Retail propane | Distillate sales
Segment information
Revenue	12,947	18,695
Operating segment | Retail propane | Other revenues
Segment information
Revenue	8,315	7,181
Operating segment | Refined products and renewables | Service fees
Segment information
Revenue	28,073
Operating segment | Refined products and renewables | Refined products sales
Segment information
Revenue	1,708,949	986,223
Operating segment | Refined products and renewables | Renewables sales
Segment information
Revenue	106,153	131,274
Operating segment | Corporate and other
Segment information
Revenue		1,461
Elimination of intersegment sales
Segment information
Revenue	$ (17,679)	$ (51,139)