Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	Sep. 27, 2020	Dec. 29, 2019
Goodwill [Line Items]
Gross value	$ 728.6	$ 708.9
Less accumulated impairment	253.3	253.3
Net	475.3	455.6
Kratos Government Solutions
Goodwill [Line Items]
Gross value	607.9	597.8
Less accumulated impairment	239.5	239.5
Net	368.4	358.3
Unmanned Systems
Goodwill [Line Items]
Gross value	120.7	111.1
Less accumulated impairment	13.8	13.8
Net	$ 106.9	$ 97.3

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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