Equity Method Investments (Tables)

3 Months Ended

Mar. 31, 2018

Schedule of Equity Method Investments [Line Items]

Schedule of equity method investments [Table Text Block]

Cash distributions received from equity method investments consisted of the following (in thousands):

	Three Months Ended March 31,
	2018		2017
White Cliffs Pipeline, L.L.C.	$	19,150	$	18,190
Glass Mountain Pipeline, LLC	—		3,503
Total cash distributions received from equity method investments	$	19,150	$	21,693

Our equity method investments consisted of the following (in thousands):

	March 31, 2018		December 31, 2017
White Cliffs Pipeline, L.L.C.	$	260,126	$	266,362
NGL Energy Partners LP	18,928		18,919
Total equity method investments	$	279,054	$	285,281

Our earnings from equity method investments consisted of the following (in thousands):

	Three Months Ended March 31,
	2018		2017
White Cliffs Pipeline, L.L.C.	$	12,605	$	15,193
Glass Mountain Pipeline, LLC	—		1,895
NGL Energy Partners LP	9		3
Total earnings from equity method investments	$	12,614	$	17,091

White Cliffs Pipeline, L.L.C. [Member]

Schedule of Equity Method Investments [Line Items]

Schedule of equity method investments [Table Text Block]

Certain unaudited summarized income statement information of White Cliffs for the three months ended March 31, 2018 and 2017, is shown below (in thousands):

	Three Months Ended March 31,
	2018		2017
Revenue	$	40,391	$	50,184
Cost of products sold, exclusive of depreciation and amortization shown below	$	384	$	4,113
Operating, general and administrative expenses	$	5,402	$	6,240
Depreciation and amortization expense	$	9,592	$	9,256
Net income	$	25,014	$	30,575