v3.8.0.1

Equity Method Investments (Details) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Feb. 10, 2017 USD ($) shares | Feb. 06, 2017 | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2016 mi
Equity Method Investment |  |  |  |  |  |  |
Contribution to joint venture |  |  |  |  | $ 216,776 | $ 45,044 |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Balance at beginning of period |  |  |  |  | 68,299 |  |
Initial investment |  |  |  |  | 153,770 |  |
Additional investment |  |  |  |  | 63,006 |  |
Equity in net income (loss) of unconsolidated affiliates |  |  | $ 7,033 | $ 1,544 | 12,887 | $ 2,027 |
Distributions from unconsolidated affiliates |  |  |  |  | (10,120) |  |
Balance at end of period |  |  | 287,842 |  | 287,842 |  |
Common Unitholders Public |  |  |  |  |  |  |
Equity Method Investment |  |  |  |  |  |  |
Sale of units to public (in shares) | shares | 6,900,000 |  |  |  |  |  |
Net proceeds from sale of units | $ 223,000 |  |  |  |  |  |
Appalachia Joint venture |  |  |  |  |  |  |
Equity Method Investment |  |  |  |  |  |  |
Ownership percentage |  | 50.00% |  |  |  |  |
Percentage of interest held by joint venture in third party fractionator in Ohio |  | 33.33% |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Initial investment |  |  |  |  | 153,770 |  |
Additional investment |  |  |  |  | 63,006 |  |
Equity in net income (loss) of unconsolidated affiliates |  |  |  |  | 5,218 |  |
Distributions from unconsolidated affiliates |  |  |  |  | (1,660) |  |
Balance at end of period |  |  | $ 220,334 |  | $ 220,334 |  |
Appalachia Joint venture | MarkWest |  |  |  |  |  |  |
Equity Method Investment |  |  |  |  |  |  |
Ownership percentage |  | 50.00% | 50.00% |  | 50.00% |  |
Stonewall Gas Gathering LLC |  |  |  |  |  |  |
Equity Method Investment |  |  |  |  |  |  |
Ownership percentage |  |  | 15.00% |  | 15.00% |  | 15.00%
Number of miles | mi |  |  |  |  |  |  | 67
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Balance at beginning of period |  |  |  |  | $ 68,299 |  |
Equity in net income (loss) of unconsolidated affiliates |  |  |  |  | 7,669 |  |
Distributions from unconsolidated affiliates |  |  |  |  | (8,460) |  |
Balance at end of period |  |  | $ 67,508 |  | $ 67,508 |  |

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- Definition Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21D -URI http://asc.fasb.org/extlink&oid=98514028&loc=SL94080555-108585 + Details
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- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(f)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Definition Monetary value of the issuance of new units of limited partnership interest in a public offering, net of offering costs. This is a parenthetical disclosure. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 + Details
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