Rose Rock Midstream, L.P. (Details 3) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summarized Balance Sheet Information
Other current assets	$ 19,387	$ 20,017
Property, plant and equipment	1,566,821	1,256,825
Equity method investments	551,078	577,920
Goodwill	48,032	58,326	$ 62,021	$ 9,884
Other noncurrent assets	62,155	44,386
Total assets	2,870,690	2,589,802
Current liabilities	377,027	391,662
Long-term debt	1,074,597	767,092
Total liabilities and owners’ equity	2,870,690	2,589,802
Rose Rock Midstream L P [Member]
Summarized Balance Sheet Information
Cash	9,059	3,625
Other current assets	310,555	271,144
Property, plant and equipment	441,596	396,066
Equity method investments	438,291	269,635
Goodwill	26,628	36,116
Other noncurrent assets	31,702	29,677
Total assets	1,257,831	1,006,263
Current liabilities	283,029	265,682
Long-term debt	744,597	432,092
Partners’ capital attributable to SemGroup	149,376	238,560
Partners’ capital attributable to noncontrolling interests	80,829	69,929
Total liabilities and owners’ equity	$ 1,257,831	$ 1,006,263