XML 106 R53.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Employee Postretirement Benefits Employee Postretirement Benefits (Pension Plans with a PBO in Excess of Plan Assets) (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
PBO | $ 2,303 | $ 2,038
Fair value of plan assets | $ 2,039 | $ 1,727

X
- Definition Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920 + Details
Name: | us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920 + Details
Name: | us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant