Rose Rock Midstream, L.P. (Details 2) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Distributions paid or to be paid
Distribution per unit	$ 0.4300	$ 0.4025	$ 0.3725	$ 0.0670	[1]
Record Date	May 06, 2013	Feb. 04, 2013	May 07, 2012	Feb. 03, 2012
Distribution Date	May 15, 2013	Feb. 14, 2013	May 15, 2012	Feb. 13, 2012
Partners' Capital Account, Distributions	$ 8,941	$ 8,331	$ 6,377	$ 1,147
SemGroup [Member] | Common Units [Member]
Distributions paid or to be paid
Limited partner distributions	1,242	1,163	517	93
SemGroup [Member] | Subordinated Units [Member]
Distributions paid or to be paid
Limited partner distributions	3,607	3,377	3,125	561
Noncontrolling Interest [Member]
Distributions paid or to be paid
Limited partner distributions	3,872	3,624	2,607	470
SemGroup [Member]
Distributions paid or to be paid
General partner distributions	179	167	128	23
Incentive distributions	$ 41	$ 0	$ 0	$ 0

[1] *Minimum quarterly distribution for quarter ended December 31, 2011 was prorated for the period beginning immediately after the closing of Rose Rock’s IPO, December 14, 2011 through December 31, 2011.