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Employee Benefit Plans Level 4 Defined Benefit Plan, Information about Plan Assets (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | $ 1,767 |  | $ 1,493 |  |
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation |  | 5,650 |  | 5,734 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 4,422 |  | 3,911 |  | $ 4,146
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | (171) |  | (66) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 695 |  | 486 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | (390) |  | (648) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | 24 |  | (93) |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Accumulated Benefit Obligation |  | 5,650 |  | 5,732 |  |
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Fair Value of Plan Assets |  | 4,678 |  | 4,430 |  |
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 320 |  | 375 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 201 |  | 139 |  | 112
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | (1) |  | 28 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 15 |  | 20 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | (78) |  | (238) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | (3) |  | 5 |  |
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  |  |  | (14) |  |
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  |  |  | 12 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  |  |  | 19 |  | 34
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  |  |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  |  |  | (11) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  |  |  | (2) |  |
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  |  |  | (6) |  |
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  |  |  | 14 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  |  |  | 24 |  | 28
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  |  |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 14 |  | 14 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  |  |  | (2) |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  |  |  | 4 |  |
Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  |  |  | 1 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  |  |  | 5 |  | 5
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  |  |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  |  |  | (1) |  |
Mortgage Loans on Real Estate, Loan Category [Domain] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 |  | 0 |  |
Other Fixed Income [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 1 |  | 3 |  |
Other Pension Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 1 |  | 1 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 1 |  | 2 |  | 3
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 1 |  | (1) |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 1 |  | (1) |  |
Other Pension Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 0 |  | 1 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 1 |  | 3 |  | 3
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | (2) |  | 1 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 0 |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 0 |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 0 |  | 0 |  | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 0 |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 1 |  | 0 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 1 |  | 0 |  | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 0 |  | 0 |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 0 |  |  |  |
Other Pension Plan [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 2 |  | 2 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 3 |  | 5 |  | 6
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | (2) |  | 1 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 1 |  | (1) |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 1 |  | (1) |  |
Pension Plan [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plan, Assets for Plan Benefits | [1] | $ 4,641 |  | $ 4,470 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Asset Equity Securities |  | 24.00% |  | 23.00% |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Asset Debt Securities |  | 76.00% |  | 77.00% |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Asset Other |  | 0.00% |  | 0.00% |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Assets |  | 100.00% |  | 100.00% |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 4,214 |  | $ 3,830 |  |
Investment Payables Net of Investment Receivables |  | 2 |  | 67 |  |
Interest Receivables |  | 39 |  | 27 |  |
Defined Benefit Plan, Settlements, Benefit Obligation |  | 0 |  | 0 |  |
Pension Plan [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value | [1] | 993 |  | 821 |  |
Pension Plan [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | (14) |  | 23 |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value | [1] | 3,054 |  | 2,902 |  |
Pension Plan [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 109 |  | 84 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 167 |  | 107 |  | 76
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 1 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  |  |  | (17) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | (23) |  | 14 |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 5 |  | (5) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | (3) |  | (4) |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value | [1] | 167 |  | 107 |  |
Pension Plan [Member] | Short-term Investments [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 311 |  | 281 |  |
Pension Plan [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 12 |  | 7 |  |
Pension Plan [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 299 |  | 274 |  |
Pension Plan [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 0 |  | 0 |  |
Pension Plan [Member] | Equity Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum |  | 10.00% |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum |  | 30.00% |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 300 |  | 385 |  |
Pension Plan [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 300 |  | 298 |  |
Pension Plan [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 87 |  |
Pension Plan [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 0 |  | 0 |  |
Pension Plan [Member] | Fixed Income Funds [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum |  | 50.00% |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum |  | 70.00% |  |  |  |
Pension Plan [Member] | Alternative Assets [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum |  | 0.00% |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum |  | 40.00% |  |  |  |
Pension Plan [Member] | Corporate Debt Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 1,482 |  | 941 |  |
Pension Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | (11) |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 1,469 |  | 922 |  |
Pension Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 15 |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 13 |  | 19 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | (10) |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | 0 |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 13 |  | 19 |  |
Pension Plan [Member] | Residential Mortgage Backed Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 276 |  | 266 |  |
Pension Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | (2) |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 266 |  | 242 |  |
Pension Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 0 |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 10 |  | 24 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 0 |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 2 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | 0 |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 10 |  | 24 |  |
Pension Plan [Member] | US Treasury Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 722 |  | 1,048 |  |
Pension Plan [Member] | US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 69 |  | 16 |  |
Pension Plan [Member] | US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 649 |  | 1,029 |  |
Pension Plan [Member] | US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 4 |  | 3 |  |
Pension Plan [Member] | Foreign Government Debt Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 38 |  | 54 |  |
Pension Plan [Member] | Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 37 |  | 49 |  |
Pension Plan [Member] | Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 0 |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 1 |  | 5 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | (4) |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | 0 |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 1 |  | 5 |  |
Pension Plan [Member] | Mortgage Loans on Real Estate, Loan Category [Domain] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 70 |  | 54 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 121 |  | 54 |  | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | (3) |  | 0 |  |
Pension Plan [Member] | Other Fixed Income [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 114 | [2] | 106 | [3] |
Pension Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 | [2] | 0 | [3] |
Pension Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | (1) |  | (3) |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 96 | [2] | 105 | [3] |
Pension Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases |  | 24 |  | 3 |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | 22 |  | 5 |  | $ 9
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  | 1 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  | (9) |  | (1) |  |
Defined Benefit Plan, Transfers Between Measurement Levels |  | 3 |  | 1 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) |  | 0 |  | (1) |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 18 | [2] | 1 | [3] |
Pension Plan [Member] | Hedge Funds [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 340 |  | 620 |  |
Pension Plan [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Commercial Mortgage Backed Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 131 |  | 183 |  |
Pension Plan [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 131 |  | 183 |  |
Pension Plan [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 121 |  | 54 |  |
Pension Plan [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 121 |  | 54 |  |
Pension Plan [Member] | Private Equity Funds [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 87 |  | 20 |  |
Pension Plan [Member] | Private Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Private Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | 0 |  |
Pension Plan [Member] | Private Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | $ 0 |  |
Other Postretirement Benefit Plan [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plan, Future Amortization of Prior Service Cost (Credit) |  | $ (7) |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Asset Equity Securities |  | 27.00% |  | 25.00% |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Asset Debt Securities |  | 73.00% |  | 75.00% |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Asset Other |  | 0.00% |  | 0.00% |  |
Defined Benefit Plan Weighted Average Allocation Percentage of Assets |  | 100.00% |  | 100.00% |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 137 | [4] | $ 171 | [5] |
Investment Payables Net of Investment Receivables |  | 1 |  | 5 |  |
Interest Receivables |  | 1 |  | 1 |  |
Defined Benefit Plan, Settlements, Benefit Obligation |  | 1 |  | 0 |  |
Other Postretirement Benefit Plan [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 46 | [4] | 41 | [5] |
Other Postretirement Benefit Plan [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 88 |  | 125 |  |
Other Postretirement Benefit Plan [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 3 | [4] | 5 | [5] |
Other Postretirement Benefit Plan [Member] | Short-term Investments [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 4 |  | 16 |  |
Other Postretirement Benefit Plan [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 4 |  |  |  |
Other Postretirement Benefit Plan [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 0 |  | 16 |  |
Other Postretirement Benefit Plan [Member] | Equity Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum |  | 15.00% |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum |  | 45.00% |  |  |  |
Other Postretirement Benefit Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 37 |  | 41 |  |
Other Postretirement Benefit Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 37 |  | 41 |  |
Other Postretirement Benefit Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 0 |  | 0 |  |
Other Postretirement Benefit Plan [Member] | Fixed Income Funds [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum |  | 55.00% |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum |  | 85.00% |  |  |  |
Other Postretirement Benefit Plan [Member] | Alternative Assets [Member] |  |  |  |  |  |
Defined Benefit Plan, Assets, Target Allocations [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum |  | 0.00% |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum |  | 0.00% |  |  |  |
Other Postretirement Benefit Plan [Member] | Corporate Debt Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | $ 36 |  | 38 |  |
Other Postretirement Benefit Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 35 |  | 36 |  |
Other Postretirement Benefit Plan [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 1 |  | 2 |  |
Other Postretirement Benefit Plan [Member] | Residential Mortgage Backed Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 25 |  | 30 |  |
Other Postretirement Benefit Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 24 |  | 27 |  |
Other Postretirement Benefit Plan [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 1 |  | 3 |  |
Other Postretirement Benefit Plan [Member] | US Treasury Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 19 |  | 23 |  |
Other Postretirement Benefit Plan [Member] | US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 5 |  |  |  |
Other Postretirement Benefit Plan [Member] | US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 14 |  | 23 |  |
Other Postretirement Benefit Plan [Member] | Foreign Government Debt Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 2 |  | 2 |  |
Other Postretirement Benefit Plan [Member] | Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 2 |  | 2 |  |
Other Postretirement Benefit Plan [Member] | Other Fixed Income [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 5 |  | 7 |  |
Other Postretirement Benefit Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 4 |  | 7 |  |
Other Postretirement Benefit Plan [Member] | Other Fixed Income [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 1 |  |  |  |
Other Postretirement Benefit Plan [Member] | Commercial Mortgage Backed Securities [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 9 |  | 14 |  |
Other Postretirement Benefit Plan [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 9 |  | 14 |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 696 |  | 512 |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 589 |  | 500 |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 107 |  | 11 |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Large Capitalization [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  | $ 1 |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Mid Capitalization [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 23 |  |  |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Mid Capitalization [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 23 |  |  |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Mid Capitalization [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  |  |  |
UNITED STATES | Pension Plan [Member] | Equity Securities [Member] | Mid Capitalization [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques and Inputs [Abstract] |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Net Of Certain Items Not Carried At Fair Value |  | 0 |  |  |  |
Hartford Life Insurance Company [Member] | Separate Accounts [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plan, Assets for Plan Benefits |  | $ 4,800 |  |  |  |
[1] | Excludes approximately $2 of investment payables net of investment receivables that are excluded from this disclosure requirement because they are trade receivables in the ordinary course of business where the carrying amount approximates fair value. Also excludes approximately $39 of interest receivable
[2] | Includes ABS, municipal bonds, and CDOs.
[3] | Includes ABS,municipal bonds, and CDOs.
[4] | Excludes approximately $1 of investment payables net of investment receivables that are excluded from this disclosure requirement because they are trade receivables in the ordinary course of business where the carrying amount approximates fair value. Also excludes approximately $1 of interest receivable.
[5] | Excludes approximately $5 of investment payables net of investment receivables that are not carried at fair value and approximately $1 of interest receivable carried at fair value.

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- Definition Defined benefit plan fair value of plan assets net of certain items not carried at fair value. + References No definition available. + Details
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- Definition Defined benefit plan weighted average allocation percentage of asset debt securities. + References No definition available. + Details
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- Definition Defined benefit plan weighted average allocation percentage of asset equity securities. + References No definition available. + Details
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- Definition Defined benefit plan weighted average allocation percentage of asset other. + References No definition available. + Details
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- Definition Defined benefit plan weighted average allocation percentage of assets total. + References No definition available. + Details
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- Definition This represents the entire assets recognized in the balance sheet that are associated with the defined benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.10) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position. + References No definition available. + Details
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- Definition If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=73719040&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=73719040&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=73719040&loc=d3e4179-114921 + Details
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- Definition The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 + Details
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- Definition Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02)(C) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(iv)(02)(C) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 + Details
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- Definition Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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