Retirement Benefits Accumulated Benefit Obligations in Excess of Fair Value (Details 4) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Pension plans with accumulated benefit obligations in excess of fair value of plan assets (Table Amounts) [Abstract]
Projected benefit obligation	$ 36,524	$ 37,681
Accumulated benefit obligation	35,994	37,135
Fair value of plan assets	$ 33,410	$ 31,741

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920

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