v3.19.2

Organization and Basis of Presentation, Fair Value (Details) - USD ($) $ in Millions |  | 3 Months Ended | 6 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 02, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Jun. 30, 2018 | Sep. 30, 2018 | Jan. 01, 2019 | Dec. 31, 2018
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability |  |  | $ 2 | $ 0 | [1] |  |  |
Finance Lease, Liability |  |  | $ 13 |  |  |  |  |
Limited Partners' Capital Account, Units Outstanding |  |  | 245,630,444 |  |  | 245,000,000 |  | 245,493,184
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage |  |  | 64.00% |  |  | 64.00% |  |
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest |  |  |  |  |  | 100.00% |  |
Net Cash Provided by (Used in) Operating Activities, Continuing Operations |  |  | $ 483 | 547 | [2] |  |  |
Net Cash Provided by (Used in) Investing Activities |  |  | (265) | (748) | [2] |  |  |
Debt, carrying value |  |  | 5,300 |  |  |  |  | $ 5,000
Debt, fair value |  |  | $ 5,400 |  |  |  |  | $ 4,900
Limited Partner Units, Public |  |  |  |  |  |  |  |
Limited Partners' Capital Account, Units Outstanding |  |  | 89,457,316 |  |  |  |  |
Limited Partner Units, Affiliate |  |  |  |  |  |  |  |
Limited Partners' Capital Account, Units Outstanding |  |  | 156,173,128 |  |  | 156,000,000 |  |
Accounting Standards Update 2016-02 |  |  |  |  |  |  |  |
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability | $ 131 |  |  |  |  |  |  |
Finance Lease, Liability |  |  |  |  |  |  | $ 133 |
Predecessors |  |  |  |  |  |  |  |
Net Cash Provided by (Used in) Operating Activities, Continuing Operations |  |  |  | 86 |  |  |  |
Net Cash Provided by (Used in) Investing Activities |  |  |  | $ 422 |  |  |  |
Subsequent Event | MPLX Merger | Limited Partner Units, Public |  |  |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares |  | 1.135 |  |  |  |  |  |
Subsequent Event | MPLX Merger | Limited Partner Units, Affiliate |  |  |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares |  | 1.0328 |  |  |  |  |  |
[1] | Adjusted to include the historical results of the Predecessors. See Note 1 for further discussion.
[2] | Adjusted to include the historical results of the Predecessors. See Note 1 for further discussion.

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