Postretirement Benefits - Narrative (Details) employees in Thousands, $ in Millions	3 Months Ended		12 Months Ended
	Jul. 31, 2018 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2020 USD ($)	Oct. 31, 2019 USD ($) employees	Oct. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Jan. 31, 2019 USD ($)	Jul. 31, 2017 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption				$ 37			$ 27
Liability, Other Postretirement Defined Benefit Plan, Noncurrent								$ 66
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	$ 21			11	$ 2
Defined Contribution Plan, Administrative Expense	23			142	9
Defined Benefit Plan, Cost of Providing Special and Contractual Termination Benefits		$ 1
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)				263	105	$ 118
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation				3,325	3,065
Defined Benefit Plan, Accumulated Benefit Obligation				3,300
Restructuring Charges				12	(1)	3
Defined Contribution Plan, Cost				35	33	29
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation				3,307	3,051
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets				1,991	1,865
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)				$ 17	16
Number Of Former Employees And Their Beneficiaries Included In Retiree Population | employees				30
Defined benefit plan, weighted average rate of increase in in per capita cost percent of benefit obligation				14.40%
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	9
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	10
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment	2
Income (Loss) from Continuing Operations before Income Taxes, Domestic				$ 5		28
Profit sharing accrual				21	30
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contribution by Employer, Net				136	132
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)				(405)	251
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months				258
Fair Value of Plan Assets				$ 2,013	$ 2,162	$ 2,363
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets				7.40%	7.20%	7.20%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate				3.10%	4.40%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate				4.60%	3.90%	3.90%
Defined Benefit Plan, Assumptions Used in Calculating Interest Cost, Discount Rate				4.00%	3.00%	2.80%
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year				$ 1
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)				232	$ 72	$ 121
Employer contributions				140
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)				266	$ 286
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year				$ 97
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase				3.50%	3.50%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase				3.50%	3.50%	3.50%
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				$ 2,011	$ 2,144
Defined Benefit Plan, Expected Future Benefit Payment, Year Two				253
Defined Benefit Plan, Expected Future Benefit Payment, Year Three				246
Defined Benefit Plan, Expected Future Benefit Payment, Year Four				240
Defined Benefit Plan, Expected Future Benefit Payment, Year Five				233
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter				1,057
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment				0	0	$ 0
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contribution by Employer, Net				1	1
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)				138	159
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months				66
Fair Value of Plan Assets				283	$ 297	$ 333
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components				$ 8
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets				7.50%	7.50%	7.50%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate				3.10%	4.40%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate				4.60%	3.90%	4.00%
Defined Benefit Plan, Assumptions Used in Calculating Interest Cost, Discount Rate				4.10%	3.10%	2.90%
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year				$ 0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)				31	$ 33	$ (3)
Employer contributions				1
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year				1
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)				144	$ 160
Defined benefit plan, benefits paid from Company assets				37
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year				$ (1)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase				0.00%	0.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase				0.00%	0.00%	0.00%
Defined benefit plan, weighted average rate of increase in in per capita cost percent of benefit obligation				90.00%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate				5.00%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year				10.10%
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components				$ (7)
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation				141
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation				(117)
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				283	$ 297
Defined Benefit Plan, Expected Future Benefit Payment, Year Two				69
Defined Benefit Plan, Expected Future Benefit Payment, Year Three				73
Defined Benefit Plan, Expected Future Benefit Payment, Year Four				76
Defined Benefit Plan, Expected Future Benefit Payment, Year Five				77
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter				356
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	4
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment				0	0	$ (58)
Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				851	861
Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				132	138
Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				860	973
Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				77	78
Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Alternative Investments, Fair Value of Plan Assets, NAV				300	310
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				0	0
Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investments, Fair Value of Plan Assets, NAV				74	81
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables				0	0
Cash and Cash Equivalents [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				68	77
Cash and Cash Equivalents [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				8	11
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				68	77
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				8	11
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
US Treasury Bond Securities [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				58	61
US Treasury Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
US Treasury Bond Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				58	61
US Treasury Bond Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Corporate Bond Securities [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
U.S. Equity [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				281	293
U.S. Equity [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				58	59
U.S. Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				281	293
U.S. Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				58	59
U.S. Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
U.S. Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
U.S. Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
U.S. Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Canadian Equity Other [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	16
Canadian Equity Other [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	16
Canadian Equity Other [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Canadian Equity Other [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
International Equity Other [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				283	270
International Equity Other [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				57	59
International Equity Other [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				283	270
International Equity Other [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				57	59
International Equity Other [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
International Equity Other [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
International Equity Other [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
International Equity Other [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Fixed Income, Multi Asset Credit [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				28	26
Fixed Income, Multi Asset Credit [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				9	9
Fixed Income, Multi Asset Credit [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				19	17
Fixed Income, Multi Asset Credit [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Global Equity [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				219	205
Global Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				219	205
Global Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Global Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Fixed Income, Long Duration Credit [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				296	283
Fixed Income, Long Duration Credit [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Fixed Income, Long Duration Credit [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				296	283
Fixed Income, Long Duration Credit [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Government [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				173	156
Government [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Government [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				173	156
Government [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Fixed Income, High Yield [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				154	157
Fixed Income, High Yield [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Fixed Income, High Yield [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				154	157
Fixed Income, High Yield [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Fixed Income, Canadian Bond [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				20	194
Fixed Income, Canadian Bond [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Fixed Income, Canadian Bond [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				20	194
Fixed Income, Canadian Bond [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Global Real Estate [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				138	135
Global Real Estate [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Global Real Estate [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				138	135
Global Real Estate [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Global Infrastructure [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	9
Global Infrastructure [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Global Infrastructure [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Global Infrastructure [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	9
Commodities Investment [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				34	45
Commodities Investment [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Commodities Investment [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Commodities Investment [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Commodities Investment [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Commodities Investment [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Commodities Investment [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				34	45
Commodities Investment [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				0	0
Insurance Linked Securities [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				6	8
Insurance Linked Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Insurance Linked Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Insurance Linked Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				6	8
Hedge Funds [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				187	202
Hedge Funds [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				37	39
Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				187	202
Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				37	39
Private Equity Funds [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				23	32
Private Equity Funds [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				5	8
Private Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Private Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Private Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Private Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Private Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				23	32
Private Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				5	8
Real Estate [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				9	0
Real Estate [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Real Estate [Member] | Fair Value, Inputs, Level 2 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Real Estate [Member] | Fair Value, Inputs, Level 3 [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				9	0
Common Stock | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				26	26
Common Stock | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Common Stock | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Common Stock | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets				0	0
Alternative Investments, Fair Value of Plan Assets, NAV				$ 26	26
Return-seeking Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage				70.00%
Liability-hedging Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage				30.00%
Melrose Park [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	$ 91
Scenario, Forecast [Member] | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			$ 190
Accounting Standards Update 2017-07 [Member]
Defined Benefit Plan Disclosure [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption					$ 94	$ 127