Debt (Details) (USD $) In Millions, unless otherwise specified	Mar. 30, 2012	Dec. 31, 2011
Components of debt and reconciliation to carrying amount
Borrowings under Amended and Restated Revolving Credit Facility	$ 4
L-3 Communications [Member]
Components of debt and reconciliation to carrying amount
Borrowings under Amended and Restated Revolving Credit Facility
3.95% Senior Notes due 2016	500	500
5.20% Senior Notes due 2019	1,000	1,000
4.75% Senior Notes due 2020	800	800
4.95% Senior Notes due 2021	650	650
6 3/8% Senior Subordinated Notes due 2015	500	500
Subtotal	3,450	3,450
L-3 Holdings (Parent) [Member]
Components of debt and reconciliation to carrying amount
3% Convertible Contingent Debt Securities due 2035	689	689
Principal amount of long-term debt	4,139	4,139
Less: Unamortized discounts	(13)	(14)
Carrying amount of long-term debt	$ 4,126	$ 4,125