Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2025	Jun. 30, 2024	Jun. 29, 2025	Jun. 30, 2024
Disaggregation of Revenue [Line Items]
Total Revenues	$ 351.5	$ 300.1	$ 654.1	$ 577.3
Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	278.3	214.3	517.8	432.1
Kratos Government Solutions | U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	186.7	129.2	336.1	264.3
Kratos Government Solutions | International
Disaggregation of Revenue [Line Items]
Total Revenues	52.2	41.3	107.5	92.0
Kratos Government Solutions | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	39.4	43.8	74.2	75.8
Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	73.2	85.8	136.3	145.2
Unmanned Systems | U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	62.0	66.2	118.1	122.0
Unmanned Systems | International
Disaggregation of Revenue [Line Items]
Total Revenues	9.0	18.8	14.8	21.2
Unmanned Systems | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	2.2	0.8	3.4	2.0
Fixed price | Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	170.3	139.7	336.8	285.4
Fixed price | Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	59.2	71.7	111.8	115.6
Cost plus fee | Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	94.8	58.2	152.8	116.8
Cost plus fee | Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	13.1	12.6	22.9	26.1
Time and materials | Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	13.2	16.4	28.2	29.9
Time and materials | Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	$ 0.9	$ 1.5	$ 1.6	$ 3.5