UNAUDITED CONDESNED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues:
Gathering services and other fees	$ 54,831	$ 47,914	$ 104,903	$ 93,888
Natural gas, NGLs and condensate sales and other	26,190	23,797	52,546	40,088
Amortization of favorable and unfavorable contracts	(225)	(250)	(451)	(530)
Total revenues	80,796	71,461	156,998	133,446
Costs and expenses:
Cost of natural gas and NGLs	16,378	13,438	31,660	21,403
Operation and maintenance	19,859	18,371	39,040	35,950
General and administrative	8,690	8,406	16,576	14,973
Transaction costs	76	2,435	612	2,473
Depreciation and amortization	20,480	16,801	40,122	30,714
Total costs and expenses	65,483	59,451	128,010	105,513
Other (expense) income	(5)	1	(4)	2
Interest expense	(10,803)	(3,023)	(17,947)	(4,903)
Income before income taxes	4,505	8,988	11,037	23,032
Income tax expense	(469)	(221)	(628)	(402)
Net income	4,036	8,767	10,409	22,630
Less: net income attributable to Summit Investments (Note 1)	0	699	2,828	2,082
Net income attributable to SMLP	4,036	8,068	7,581	20,548
Less: net income attributable to general partner, including IDRs	801	161	1,232	411
Net income attributable to limited partners	3,235	7,907	6,349	20,137
Weighted-average limited partner units outstanding
Cash distributions declared per common unit (in dollars per unit)	$ 0.5	$ 0.42	$ 0.98	$ 0.83
Common units
Costs and expenses:
Net income attributable to limited partners	1,891	4,012	4,398	10,127
Earnings per limited partner unit
Basic (in dollars per share)	$ 0.05	$ 0.16	$ 0.14	$ 0.41
Diluted (in dollars per share)	$ 0.05	$ 0.16	$ 0.14	$ 0.41
Weighted-average limited partner units outstanding
Basic (shares)	34,422,273	25,172,087	32,179,431	24,790,158
Diluted (shares)	34,618,506	25,281,104	32,360,022	24,871,033
Subordinated Units
Costs and expenses:
Net income attributable to limited partners	$ 1,344	$ 3,895	$ 1,951	$ 10,010
Earnings per limited partner unit
Basic (in dollars per share)	$ 0.05	$ 0.16	$ 0.08	$ 0.41
Diluted (in dollars per share)	$ 0.05	$ 0.16	$ 0.08	$ 0.41
Weighted-average limited partner units outstanding
Basic (shares)	24,409,850	24,409,850	24,409,850	24,409,850
Diluted (shares)	24,409,850	24,409,850	24,409,850	24,409,850