Newly-Formed Joint Ventures and Acquisitions - Additional Information Acquisitions (Details) - Permian Acquisition [Member] - USD ($) |
3 Months Ended | ||||
---|---|---|---|---|---|
May 30, 2017 |
Mar. 01, 2017 |
Mar. 31, 2017 |
Mar. 31, 2018 |
Dec. 31, 2017 |
|
Business Acquisition [Line Items] | |||||
Business Acquisition, Percentage of Voting Interests Acquired | 100.00% | ||||
Cash payments related to acquisition | $ 484,100,000 | ||||
Acquired debt and all other assumed liabilities included in purchase consideration | $ 90,000,000 | $ 90,000,000 | |||
Additional cash that may be paid based on potential earn-out payment | $ 373,000,000 | $ 317,000,000 | |||
Acquisition-related expenses | $ 5,100,000 | ||||
Maximum [Member] | |||||
Business Acquisition [Line Items] | |||||
Additional cash that may be paid based on potential earn-out payment | $ 935,000,000 | $ 935,000,000 |