Significant Accounting Policies - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	[1],[2]	Dec. 31, 2017	[1],[2]
Significant Accounting Policies [Line Items]
Impairment of assets	$ 0	$ 20,000,000		$ 0
Withholding tax on amounts repatriated	5.00%
PAI (Final)
Significant Accounting Policies [Line Items]
Percentage of acquired entity reported	100.00%
Percentage of acquired entity noncontrolling interest reported	20.00%
Performance Based Restricted Stock
Significant Accounting Policies [Line Items]
Stock-based compensation, vesting period	3 years
Minimum
Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	20.00%
Minimum | Stock Options
Significant Accounting Policies [Line Items]
Stock-based compensation, vesting period	2 years
Maximum
Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	50.00%
Maximum | Stock Options
Significant Accounting Policies [Line Items]
Stock-based compensation, vesting period	3 years

[1] ¹ Reclassified to conform with current presentation (see Notes C and E). 2017 revenue is presented net of $58.9 million of transportation, gathering and processing costs as historically shown prior to the adoption of ASC 606 on January 1, 2018. See Notes to Consolidated Financial Statements, page 58.

[2] Reclassified to conform with current presentation (see Note E)