Summary of Significant Accounting Policies (Unaudited) Property Plant and Equipment (Details 4) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Property, Plant, and Equipment [Abstract] | |||
| Cash flow from Sale of Equipment to a Customer | $ 371 | $ 371 | $ 0 |
| Capital Expenditures Incurred but Not yet Paid | $ 149 | $ 140 | |
| Noncash Investing and Financing Activities Related Text | During the nine months ended September 30, 2026, the company received lease incentives for landlord funded leasehold improvements of $90 million related to Aeronautics Systems real estate leases, which were recorded in PP&E and included in non-cash investing activities.Non-cash investing activities for the nine months ended September 30, 2026 and 2025 include capital expenditures incurred but not yet paid of $149 million and $140 million, respectively. | ||
| Leasehold Improvements [Member] | |||
| Property, Plant, and Equipment [Abstract] | |||
| Noncash or Part Noncash Acquisition, Fixed Assets Acquired | $ 90 | ||