Cover - USD ($) $ in Billions	12 Months Ended
	Dec. 25, 2022	Feb. 17, 2023	Jun. 24, 2022
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 25, 2022
Current Fiscal Year End Date	--12-25
Document Transition Report	false
Entity File Number	001-34460
Entity Registrant Name	KRATOS DEFENSE & SECURITY SOLUTIONS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-3818604
Entity Address, Address Line One	1 Chisholm Trail
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Round Rock
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	78681
City Area Code	512
Local Phone Number	238-9840
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	KTOS
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1.8
Entity Common Stock, Shares Outstanding		126,659,953
Documents Incorporated by Reference	Items 10, 11, 12, 13 and 14 of Part III of this annual report on Form 10-K incorporate information by reference from the registrant’s definitive proxy statement to be filed pursuant to Regulation 14A in connection with the registrant’s 2023 Annual Meeting of Stockholders or an amendment to this annual report on Form 10-K to be filed with the Securities and Exchange Commission within 120 days after the close of the fiscal year covered by this annual report on Form 10-K.
Entity Central Index Key	0001069258
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Amendment Flag	false