Rocky Flats Settlement	9 Months Ended
Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Legal Matters and Contingencies	Rocky Flats Settlement From 1975 to 1989, Rockwell International Corporation (RIC) operated the Rocky Flats facility in Colorado for the U.S. Department of Energy (DoE). In 1990, a class of landowners near Rocky Flats sued RIC and Dow Chemical, another former operator of the facility. In May 2016, the parties agreed to settle this case and the DoE authorized the settlement. Under the court approved settlement agreement, we and Dow Chemical agreed to pay $375.0 million in the aggregate to resolve the claims. Under RIC’s contract with the DoE and federal law, RIC was entitled to indemnification by the DoE for its portion of the settlement amount, which was $243.75 million. When RIC was acquired by Boeing in 1996, we agreed to indemnify Boeing for RIC’s liabilities related to Rocky Flats and received the benefits of RIC’s corresponding indemnity rights against the DoE. Pursuant to the settlement agreement, in fiscal 2016, RIC paid an initial amount of $1.25 million to the plaintiff class escrow fund. In January 2017, the DoE fulfilled its indemnification obligation by paying $243.75 million, and the full amount of RIC's obligation under the settlement agreement has now been transferred to the plaintiff class escrow account. As a result, we were not required to make any payment under the settlement agreement.

Rocky Flats Settlement

From 1975 to 1989, Rockwell International Corporation (RIC) operated the Rocky Flats facility in Colorado for the U.S. Department of Energy (DoE). In 1990, a class of landowners near Rocky Flats sued RIC and Dow Chemical, another former operator of the facility. In May 2016, the parties agreed to settle this case and the DoE authorized the settlement. Under the court approved settlement agreement, we and Dow Chemical agreed to pay $375.0 million in the aggregate to resolve the claims. Under RIC’s contract with the DoE and federal law, RIC was entitled to indemnification by the DoE for its portion of the settlement amount, which was $243.75 million. When RIC was acquired by Boeing in 1996, we agreed to indemnify Boeing for RIC’s liabilities related to Rocky Flats and received the benefits of RIC’s corresponding indemnity rights against the DoE. Pursuant to the settlement agreement, in fiscal 2016, RIC paid an initial amount of $1.25 million to the plaintiff class escrow fund. In January 2017, the DoE fulfilled its indemnification obligation by paying $243.75 million, and the full amount of RIC's obligation under the settlement agreement has now been transferred to the plaintiff class escrow account. As a result, we were not required to make any payment under the settlement agreement.