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Retirement Benefits (Schedule Of Defined Benefit Plan Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Compensation and benefits expense (Operating income) | $ (691) | $ (701) | $ (1,599) | $ (1,450)
Other net benefit credits | (65) | (63) | (131) | (123)
Pension Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 7 | 19 | 17 | 37
Interest cost | 117 | 124 | 235 | 246
Expected return on plan assets | (218) | (230) | (439) | (454)
Amortization of prior service cost | (1) | (1) | (1) | (1)
Recognized actuarial loss | 37 | 43 | 74 | 83
Net periodic benefit (credit) cost | (58) | (45) | (114) | (89)
Curtailment loss (credit) |  |  | 0 | (1)
Settlement loss |  |  | 0 | 1
Compensation and benefits expense (Operating income) | (7) | (19) | (17) | (37)
Other net benefit credits | (65) | (64) | (131) | (126)
Total (credit) cost | (58) | (45) | (114) | (89)
Postretirement Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 1 | 1 | 2 | 2
Expected return on plan assets | 0 | 0 | 0 | 0
Amortization of prior service cost | (1) | 0 | (2) | 1
Recognized actuarial loss | 0 | 0 | 0 | 0
Net periodic benefit (credit) cost | 0 | 1 | 0 | 3
Curtailment loss (credit) |  |  | 0 | 0
Settlement loss |  |  | 0 | 0
Compensation and benefits expense (Operating income) | 0 | 0 | 0 | 0
Other net benefit credits | 0 | 1 | 0 | 3
Total (credit) cost | 0 | 1 | 0 | 3
Domestic Plan | Pension Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 59 | 66 | 118 | 132
Expected return on plan assets | (90) | (90) | (179) | (179)
Amortization of prior service cost | 0 | 0 | 0 | 0
Recognized actuarial loss | 14 | 10 | 27 | 19
Net periodic benefit (credit) cost | (17) | (14) | (34) | (28)
Domestic Plan | Postretirement Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 1 | 1 | 1 | 1
Expected return on plan assets | 0 | 0 | 0 | 0
Amortization of prior service cost | (1) | 1 | (1) | 2
Recognized actuarial loss | 0 | (1) | 0 | (1)
Net periodic benefit (credit) cost | 0 | 1 | 0 | 2
Foreign Plan | Pension Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 7 | 19 | 17 | 37
Interest cost | 58 | 58 | 117 | 114
Expected return on plan assets | (128) | (140) | (260) | (275)
Amortization of prior service cost | (1) | (1) | (1) | (1)
Recognized actuarial loss | 23 | 33 | 47 | 64
Net periodic benefit (credit) cost | (41) | (31) | (80) | (61)
Curtailment loss (credit) |  |  | 0 | (1)
Settlement loss |  |  | 0 | 1
Total (credit) cost |  |  | (80) | (61)
Foreign Plan | Postretirement Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 0 | 0 | 1 | 1
Expected return on plan assets | 0 | 0 | 0 | 0
Amortization of prior service cost | 0 | (1) | (1) | (1)
Recognized actuarial loss | 0 | 1 | 0 | 1
Net periodic benefit (credit) cost | $ 0 | $ 0 | 0 | 1
Curtailment loss (credit) |  |  | 0 | 0
Settlement loss |  |  | 0 | 0
Total (credit) cost |  |  | $ 0 | $ 1

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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