Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 26, 2022	Jun. 27, 2021	Jun. 26, 2022	Jun. 27, 2021
Disaggregation of Revenue [Line Items]
Total Revenues	$ 224.2	$ 205.1	$ 420.4	$ 399.3
Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	167.8	144.8	311.4	283.1
Kratos Government Solutions | U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	104.2	91.8	193.7	184.4
Kratos Government Solutions | International
Disaggregation of Revenue [Line Items]
Total Revenues	36.1	35.8	70.8	67.5
Kratos Government Solutions | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	27.5	17.2	46.9	31.2
Kratos Government Solutions | Fixed price
Disaggregation of Revenue [Line Items]
Total Revenues	119.9	107.1	221.2	206.6
Kratos Government Solutions | Cost plus fee
Disaggregation of Revenue [Line Items]
Total Revenues	37.1	28.0	69.4	56.6
Kratos Government Solutions | Time and materials
Disaggregation of Revenue [Line Items]
Total Revenues	10.8	9.7	20.8	19.9
Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	56.4	60.3	109.0	116.2
Unmanned Systems | U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	51.9	54.4	102.0	104.0
Unmanned Systems | International
Disaggregation of Revenue [Line Items]
Total Revenues	3.6	5.5	5.4	11.8
Unmanned Systems | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	0.9	0.4	1.6	0.4
Unmanned Systems | Fixed price
Disaggregation of Revenue [Line Items]
Total Revenues	40.7	36.4	72.2	73.6
Unmanned Systems | Cost plus fee
Disaggregation of Revenue [Line Items]
Total Revenues	15.3	23.4	35.7	41.3
Unmanned Systems | Time and materials
Disaggregation of Revenue [Line Items]
Total Revenues	$ 0.4	$ 0.5	$ 1.1	$ 1.3