Condensed Combining Financial Information of L-3 Communications and Its Subsidiaries (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended			12 Months Ended
	Mar. 30, 2012		Apr. 01, 2011	Dec. 31, 2011
Operating activities:
Net cash from operating activities	$ 137		$ 220	$ 137
Investing activities:
Business acquisitions, net of cash acquired	(205)
Other investing activities	(29)		(34)
Net cash used in investing activities	(234)		(34)
Financing activities:
Proceeds from sale of senior notes			646
Redemption of senior subordinated notes			(661)
Common stock repurchased	(138)		(205)
Dividends paid on L-3 Holdings' common stock	(49)		(49)
Other financing activities	8		12
Net cash used in financing activities	(179)		(257)
Effect of foreign currency exchange rate changes on cash	5		12
Net (decrease) increase in cash	(271)		(59)
Cash and cash equivalents, beginning of the period	764		607	607
Cash and cash equivalents, end of the period	493	[1]	548	764
L-3 Holdings (Parent) [Member]
Operating activities:
Net cash from operating activities	187		265
Investing activities:
Investments in L-3 Communications	(13)		(16)
Net cash used in investing activities	(13)		(16)
Financing activities:
Redemption of senior subordinated notes			(11)
Common stock repurchased	(138)		(205)
Dividends paid on L-3 Holdings' common stock	(49)		(49)
Other financing activities	13		16
Net cash used in financing activities	(174)		(249)
L-3 Communications [Member]
Operating activities:
Net cash from operating activities	67		54
Investing activities:
Business acquisitions, net of cash acquired	(205)
Other investing activities	(16)		(18)
Net cash used in investing activities	(221)		(18)
Financing activities:
Proceeds from sale of senior notes			646
Redemption of senior subordinated notes			(650)
Dividends paid to L-3 Holdings	(187)		(265)
Investments from L-3 Holdings	13		16
Other financing activities	(32)		131
Net cash used in financing activities	(206)		(122)
Net (decrease) increase in cash	(360)		(86)
Cash and cash equivalents, beginning of the period	644		257	257
Cash and cash equivalents, end of the period	284		171
Guarantor Subsidiaries [Member]
Operating activities:
Net cash from operating activities	77		181
Investing activities:
Other investing activities	(10)		(12)
Net cash used in investing activities	(10)		(12)
Financing activities:
Other financing activities	(61)		(167)
Net cash used in financing activities	(61)		(167)
Net (decrease) increase in cash	6		2
Cash and cash equivalents, beginning of the period	2		3	3
Cash and cash equivalents, end of the period	8		5
Non-Guarantor Subsidiaries [Member]
Operating activities:
Net cash from operating activities	33		27
Investing activities:
Other investing activities	(3)		(4)
Net cash used in investing activities	(3)		(4)
Financing activities:
Other financing activities	(43)		(78)
Net cash used in financing activities	(43)		(78)
Effect of foreign currency exchange rate changes on cash	5		12
Net (decrease) increase in cash	(8)		(43)
Cash and cash equivalents, beginning of the period	229		482	482
Cash and cash equivalents, end of the period	221		439
Eliminations [Member]
Operating activities:
Net cash from operating activities	(227)		(307)
Investing activities:
Investments in L-3 Communications	13		16
Net cash used in investing activities	13		16
Financing activities:
Dividends paid to L-3 Holdings	187		265
Investments from L-3 Holdings	(13)		(16)
Other financing activities	131		110
Net cash used in financing activities	305		359
Net (decrease) increase in cash	91		68
Cash and cash equivalents, beginning of the period	(111)		(135)	(135)
Cash and cash equivalents, end of the period	$ (20)		$ (67)

[1] Unaudited