| **Significant Accounting Policies Significant Accounting Policies - Textual (Details) $ in Millions**                                                   | 12 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Accounting Policies [Abstract]**                                                                                                                      |            |   |   |
| Threshold for separate line item reporting of current assets in Consolidated Balance Sheet                                                              |            | 5.00% | 5.00% |
| Threshold for separate line item reporting of non-current assets in Consolidated Balance Sheet                                                          |            | 5.00% | 5.00% |
| Threshold for separate line item reporting of current liabilities in Consolidated Balance Sheet                                                         |            | 5.00% | 5.00% |
| Total number of sites for existence of future environment liabilities | site                                                                            |            | 61 |   |
| Number of sites owned by the company | site                                                                                                             |            | 4 |   |
| Number of sites associated with former graphics or semiconductor locations | site                                                                       |            | 48 |   |
| Treatment or disposal sites not owned by the company that containhazardous substances allegedly attributable to the company from past operations | site |            | 9 |   |
| Accrual for environment loss contingencies                                                                                                              |            | $ 106.0 |   |
| Fair value of environmental liabilities                                                                                                                 |            | 99.0 |   |
| Other environmental liabilities                                                                                                                         |            | $ 7.0 |   |
| Accrual for environment loss contingencies, Discount rate                                                                                               |            | 1.46% |   |
| Period (in years) over which expected aggregate undiscounted amount will be incurred                                                                    |            | 10 years |   |
| Expected aggregate undiscounted amount that will be incurred over the next 10 years (depending on the number of years for each site) (approximately)    |            | $ 8.0 |   |
| Estimated payments for the next five years                                                                                                              |            | 0.7 |   |
| Expected payments thereafter                                                                                                                            |            | 4.0 |   |
| **Change in Accounting Estimate [Line Items]**                                                                                                          |            |   |   |
| Reduction in interest and service cost                                                                                                                  |            | 154.0 | $ 7.0 |
| Projected benefit obligation                                                                                                                            |            | 6,390.0 | $ 6,407.0 |
| Change in Assumptions for Pension Plans | Scenario, Forecast | U.S. SRP                                                                                 |            |   |   |
| **Change in Accounting Estimate [Line Items]**                                                                                                          |            |   |   |
| Reduction in interest and service cost                                                                                                                  | $ 46.0          |   |   |
| Change in Assumptions for Pension Plans | Pro Forma | U.S. SRP                                                                                          |            |   |   |
| **Change in Accounting Estimate [Line Items]**                                                                                                          |            |   |   |
| Projected benefit obligation                                                                                                                            |            | $ 339.0 |   |
| Change in projected benefit obligation (as percent)                                                                                                     |            | 5.00% |   |

| X                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Undiscounted amount of the accrual for environmental loss contingencies estimated payments for the next five years.
+ References
No definition available.
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| - Definition
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Change in Aggregate Projected Benefit Obligation, Percentage
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                            |
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| - Definition
Number of sites associated with former graphics or semiconductor locations
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                            |
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| - Definition
Number Of Sites For Existence Of Future Environmental Liabilities.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of sites owned by the company.
+ References
No definition available.
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| - References
No definition available.
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| - Definition
Period (in years) over which expected aggregate undiscounted amount will be incurred.
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No definition available.
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| - Definition
Threshold For Separate Line Item Reporting Of Current Assets In Consolidated Balance Sheet
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No definition available.
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No definition available.
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Threshold For Separate Line Item Reporting Of Non current Assets In Consolidated Balance
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Treatment Or Disposal Sites Not Owned By Company That Contain Hazardous Substances Allegedly Attributable To Company From Past Operations
+ References
No definition available.
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| - Definition
Total costs accrued as of the balance sheet date for environmental loss contingencies.
+ References
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| - Definition
Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.
+ References
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| - Definition
Undiscounted amount of the accrual for environmental loss contingencies.
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| - Definition
Undiscounted amount of the accrual for environmental loss contingencies expected to be paid after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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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.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.
+ References
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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
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