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USD ($)

USD ($) / shares
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       In August 2010, L-3 Holdings completed its previously announced
       $1&amp;#160;billion share repurchase program, which was approved by
       its Board of Directors on November&amp;#160;24, 2008. On
       July&amp;#160;14, 2010, L-3 Holdings&amp;#8217; Board of Directors
       approved a new share repurchase program that authorizes L-3
       Holdings to repurchase up to an additional $1&amp;#160;billion of
       its outstanding shares of common stock through December&amp;#160;31,
       2012. Repurchases are made from time to time at
       management&amp;#8217;s discretion in accordance with applicable
       federal securities laws. All share repurchases of L-3 Holdings
       common stock have been recorded as treasury shares. L-3 Holdings
       repurchased 11.0&amp;#160;million shares of its common stock at an
       average price of $75.86 per share for an aggregate amount of
       approximately $834&amp;#160;million from January&amp;#160;1, 2010
       through December&amp;#160;31, 2010. At December&amp;#160;31, 2010, the
       remaining dollar value under the share repurchase program was
       $592&amp;#160;million.
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       From January&amp;#160;1, 2011 through February&amp;#160;24, 2011, L-3
       Holdings repurchased 1,367,992 shares of its common stock at an
       average price of $77.70 per share for an aggregate amount of
       approximately $106 million.
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