Strategic Action	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Strategic Action	Strategic ActionOn December 20, 2020, we announced that we entered into an agreement to acquire Aerojet Rocketdyne Holdings, Inc. (Aerojet Rocketdyne) for $56 per share in cash, which is expected to be reduced to $51 per share after Aerojet Rocketdyne pays a pre-closing special dividend to its stockholders on March 24, 2021. This represents a post-dividend equity value of approximately $4.6 billion, on a fully diluted as-converted basis, and a transaction value of approximately $4.4 billion after the assumption of Aerojet Rocketdyne’s projected net cash. We expect to finance the acquisition through a combination of cash on hand and new debt issuances. The transaction is expected to close in the second half of 2021 and is subject to the satisfaction of customary closing conditions, including regulatory approvals and approval by Aerojet Rocketdyne’s stockholders. If the acquisition agreement is terminated under certain circumstances, Aerojet Rocketdyne will be required to pay us a termination fee of $150 million. Our financial results will not include Aerojet Rocketdyne’s results until the acquisition is closed.