Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Disaggregation of Revenue [Line Items]
Total Revenues	$ 275.9	$ 274.6	$ 853.2	$ 763.3
Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	211.7	217.9	643.8	606.5
Kratos Government Solutions | U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	128.4	132.1	392.7	376.1
Kratos Government Solutions | International
Disaggregation of Revenue [Line Items]
Total Revenues	52.1	52.2	144.1	145.1
Kratos Government Solutions | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	31.2	33.6	107.0	85.3
Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	64.2	56.7	209.4	156.8
Unmanned Systems | U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	55.5	53.4	177.5	148.3
Unmanned Systems | International
Disaggregation of Revenue [Line Items]
Total Revenues	6.5	2.1	27.7	6.4
Unmanned Systems | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	2.2	1.2	4.2	2.1
Fixed price | Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	140.2	155.2	425.6	414.7
Fixed price | Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	51.0	42.4	166.6	118.3
Cost plus fee | Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	57.3	49.5	174.1	155.1
Cost plus fee | Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	11.5	11.4	37.6	30.0
Time and materials | Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	14.2	13.2	44.1	36.7
Time and materials | Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	$ 1.7	$ 2.9	$ 5.2	$ 8.5