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- Definition

Research and Development Arrangement with Federal Government, Additional Contribution

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Research and Development Arrangement with Federal Government, Agreement Value

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- Definition

Research and Development Arrangement with Federal Government, Intended Initial Contribution

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Research and Development Arrangement with Federal Government, Intended Initial Contribution, In-Kind Expense

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- Definition

Research and Development Arrangement with Federal Government, Potential Total Contribution

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- Definition

Research and Development Expense, Net of Reimbursements

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- Definition

Research and Development Expense, Not Charged To Contractual Arrangements

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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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The net amount of research and development costs incurred for a fixed-price, best-efforts research and development cost-sharing arrangement with the Federal Government.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 730
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6472174&loc=d3e58812-109433

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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Summary of Significant Accounting Policies - Narrative - AR1 Research and Development (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Nov. 30, 2015	Feb. 01, 2018
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expenses	$ 0.0	$ 0.0	$ 0.0	$ 32.1
Company
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expenses	4.6	44.6	43.0	74.4
U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
R&D expense not charged to contractual arrangements				32.1
U.S. Government Contractual Arrangements \| U.S. Air Force \| AR1 \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Net AR1 R&D costs applied to contracts		56.1
Research and development costs, net of reimbursements		88.2
Research and development expenses		32.1
Customers
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expenses	$ 33.7	$ 561.1	$ 513.0	$ 485.8
U.S. Air Force \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Investment percentage of total funding required		66.67%
Intended initial contribution		$ 174.0
U.S. Air Force \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project \| Subsequent Event
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Additional contribution required					$ 95.5
Aerojet Rocketdyne and United Launch Alliance \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Agreement value		804.0
Aerojet Rocketdyne and United Launch Alliance \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project \| Subsequent Event
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Additional contribution required					$ 47.8
Aerojet Rocketdyne Inc \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Intended initial contribution		77.3
ULA \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Intended initial contribution		6.1
Intended initial contribution in-kind expense		3.6
Aerojet Rocketdyne and Partners \| U.S. Government Contractual Arrangements \| U.S. Air Force \| Liquid Booster Engine Development Project
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Potential total contribution		$ 268.0