(14) Investments in Unconsolidated Affiliates

The Partnership has a 15% equity interest in Stonewall, which operates a 67-mile pipeline on which Antero is an anchor shipper.

On February 6, 2017, the Partnership formed the Joint Venture to develop processing and fractionation assets in Appalachia with MarkWest, a wholly owned subsidiary of MPLX. The Partnership and MarkWest each own a 50% equity interest in the Joint Venture and MarkWest operates the Joint Venture assets, which consist of processing plants in West Virginia and a one-third interest in a MarkWest fractionator in Ohio.

The Partnership’s net income includes its proportionate share of the net income of the Joint Venture and Stonewall. When the Partnership records its proportionate share of net income, it increases equity income in the consolidated statements of operations and comprehensive income and the carrying value of that investment on its balance sheet. When distributions on the Partnership’s proportionate share of net income are received, they are recorded as reductions to the carrying value of the investment on the balance sheet and are classified as cash inflows from operating activities in accordance with the nature of the distribution approach under ASU No. 2016-15. The Partnership uses the equity method of accounting to account for its investments in Stonewall and the Joint Venture because it exercises significant influence, but not control, over the entities. The Partnership’s judgment regarding the level of influence over its equity investments includes considering key factors such as its ownership interest, representation on the board of directors and participation in policy-making decisions of Stonewall and the Joint Venture.

The following table is a reconciliation of our investments in these unconsolidated affiliates:


				Total Investment
			MarkWest	in Unconsolidated
(in thousands)		Stonewall (1)	Joint Venture	Affiliates
Balance at December 31, 2016	$	68,299	—	68,299
Initial investment		—	153,770	153,770
Additional investments		—	81,234	81,234
Equity in net income of unconsolidated affiliates		10,304	9,890	20,194
Distributions from unconsolidated affiliates		(11,475)	(8,720)	(20,195)
Balance at December 31, 2017		67,128	236,174	303,302
Additional investments		—	136,475	136,475
Equity in net income of unconsolidated affiliates		10,740	29,540	40,280
Distributions from unconsolidated affiliates		(9,765)	(36,650)	(46,415)
Balance at December 31, 2018	$	68,103	365,539	433,642

(1)Distributions are net of operating and capital requirements retained by Stonewall.

(b)Summarized Financial Information of Unconsolidated Affiliates

The following tables present summarized financial information for the Partnership’s investments in unconsolidated affiliates. Summarized financial information for Stonewall is presented from May 26, 2016, the effective date the Partnership exercised its option to acquire an equity interest in the Stonewall Gathering Pipeline. Summarized financial information for the Joint Venture is presented from January 1, 2017, the effective date of the Joint Venture formation.

Combined Balance Sheets


		December 31,
(in thousands)		2017	2018
Current assets	$	62,955	90,481
Noncurrent assets		1,052,760	1,327,947
Total assets	$	1,115,715	1,418,428

Current liabilities	$	39,964	76,605
Noncurrent liabilities		219	6,986
Noncontrolling interest		179,736	172,865
Partners' capital		895,796	1,161,972
Total liabilities and partners' capital	$	1,115,715	1,418,428

Statements of Combined Operations


	Year ended December 31,
(in thousands)		2016	2017	2018
Revenues	$	51,428	119,371	189,222
Operating expenses		12,176	40,059	75,250
Income from operations		39,252	79,312	113,972
Net income attributable to the equity method investments		3,227	88,717	131,626