The amount of cash paid during the reporting period for charges associated with the mergers.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

Name:	us-gaap_PaymentsForMergerRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Organization and Operations Organization and Operations (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 08, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Sale of Stock, Price Per Share					$ 15.25
Sale of Stock, Consideration Received on Transaction	$ 5,600
Payments for Merger Related Costs		$ 0	$ 33	$ 15