Asset Retirement Obligations - Schedule of Reconciliation of Beginning and Ending Aggregate Carrying Amount of Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	$ 800,117	$ 447,270
Accretion expense	40,506	27,119	[1],[2]	$ 25,282	[1],[2]
Liabilities incurred	14,759	6,572
Liabilities assumed from acquisitions	64,810	359,643
Revisions of previous estimates	(34,371)	(20,012)
Liabilities settled	(25,544)	(11,510)
Liabilities associated with assets held for sale	(240)	0
Changes due to translation of foreign currencies	5,072	(8,965)
Balance at end of year	$ 865,109	$ 800,117		$ 447,270

[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)