Consolidated Statements of Shareholder's Equity (Parenthetical) - Cumulative Effect, Period of Adoption, Adjustment $ in Millions	Jan. 01, 2020 USD ($)
Impact of new accounting guidance	$ 140
Impact of new accounting guidance, tax	$ 21

Amount of cumulative tax effect on beginning retained earnings from change in accounting principle.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.7)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123586238&loc=d3e39076-109324

Name:	us-gaap_IncomeTaxEffectsAllocatedDirectlyToEquityCumulativeEffectOfChangeInAccountingPrinciple
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration