Acquisitions - Herley Industries, Inc. (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended		3 Months Ended								12 Months Ended							0 Months Ended				12 Months Ended			0 Months Ended
	May 14, 2012	Feb. 11, 2011	Dec. 29, 2013	Sep. 29, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 30, 2012	Sep. 30, 2012	Jun. 24, 2012	Mar. 25, 2012	Dec. 29, 2013	Dec. 30, 2012	Dec. 25, 2011	Dec. 29, 2013 Senior notes Senior Notes due June 2017	Jul. 27, 2011 Senior notes Senior Notes due June 2017	Mar. 25, 2011 Senior notes Senior Notes due June 2017	May 19, 2010 Senior notes Senior Notes due June 2017	Apr. 15, 2011 Herley Industries, Inc.	Mar. 27, 2011 Herley Industries, Inc.	Mar. 25, 2011 Herley Industries, Inc.	Feb. 11, 2011 Herley Industries, Inc.	Dec. 25, 2011 Herley Industries, Inc.	Mar. 25, 2011 Herley Industries, Inc. Senior notes Senior Notes due June 2017	Mar. 25, 2011 Herley Industries, Inc. Change in control obligations	Mar. 25, 2011 Herley Industries, Inc. Combined transaction expenses
Business Acquisition [Line Items]
Number of shares acquired																				13.2
Voting interests acquired, percentage																				94.00%
Fair value of non-controlling interest																				$ 16,900,000
Share price used to calculate fair value (in dollars per share)																				$ 19.00
Non-controlling interest, number of shares																				0.9
Aggregate amount of cash paid																		270,700,000	245,500,000	45,000,000
Conversion to Kratos common stock ratio																				1.3495
Common stock issued to assume the Herley Options (in shares)																				0.8
Common stock issued to assume the Herley Options, fair value																				1,900,000
Purchase price																				272,500,000
Change in control obligations assumed																								4,000,000
Combined transaction expenses																									11,100,000
Common stock issued in acquisition, shares																					4.9
Purchase price (in dollars per share)																					$ 13.25
Gross proceeds from issuance of common stock	100,000,000	64,800,000																			64,800,000
Proceeds from the issuance of common stock, net of issuance costs	97,000,000	61,100,000									0	97,000,000	61,100,000								61,100,000
Principal			629,800,000				630,700,000				629,800,000	630,700,000		625,000,000	115,000,000	285,000,000	225,000,000						285,000,000
Issuance premium, percentage																							107.00%
Number of years in business																				45 years
Revenues											100,900,000	116,200,000	54,300,000									150,800,000
Operating income (loss)			$ 5,400,000	$ 6,100,000	$ 8,900,000	$ 11,400,000	$ (80,300,000)	$ 14,100,000	$ 7,400,000	$ 9,100,000	$ 31,800,000	$ (49,700,000)	$ 29,500,000									$ 12,700,000