2.2.0.7 true L-3 Holdings' Earnings Per Common Share (Details) (USD $) 0612 - Disclosure - L-3 Holdings' Earnings Per Common Share (Details) true false Share data in Millions, except Per Share data false false 1 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 $ false 2 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ false 3 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ false 4 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ false 5 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ 2 Reconciliation of net income: 2 lll_ReconciliationOfNetIncome lll false na duration Reconciliation of net income. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string Reconciliation of net income. false 3 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 true true false false 231000000 231000000 false false false 2 true true false false 227000000 227000000 false false false 3 true true false false 453000000 453000000 false false false 4 true true false false 428000000 428000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) false 4 Net income attributable to noncontrolling interests 2 us-gaap_NetIncomeLossAttributableToNoncontrollingInterest us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false -3000000 -3000000 false false false 2 false true false false -2000000 -2000000 false false false 3 false true false false -4000000 -4000000 false false false 4 false true false false -4000000 -4000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The portion of net income (loss) attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 false 5 Net income allocable to participating securities 2 lll_NetIncomeAllocableToParticipatingSecurities lll false debit duration Net income allocable to participating securities. false false false false false false false false false false false verboselabel false 1 false true false false -1000000 -1000000 false false false 2 false true false false -2000000 -2000000 false false false 3 false true false false -3000000 -3000000 false false false 4 false true false false -4000000 -4000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Net income allocable to participating securities. No authoritative reference available. false 6 Net income allocable to L-3 Holdings' common shareholders 2 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic us-gaap true credit duration No definition available. false false false false false false false false false false true negatedtotal false 1 false true false false 227000000 227000000 false false false 2 false true false false 223000000 223000000 false false false 3 false true false false 446000000 446000000 false false false 4 false true false false 420000000 420000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 9 true 7 Basic: 2 us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 8 Weighted average common shares outstanding 2 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic us-gaap true na duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 115400000 115.4 false false false 2 false true false false 116500000 116.5 false false false 3 false true false false 115700000 115.7 false false false 4 false true false false 117400000 117.4 false false false 5 false false false false 0 0 false false false xbrli:sharesItemType shares Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 171 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 40 -Subparagraph a Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 8 false 9 Basic earnings per share: 2 us-gaap_EarningsPerShareBasicAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 10 Net income 2 us-gaap_EarningsPerShareBasic us-gaap true na duration No definition available. false false false false false false false false false false false terselabel true 1 true true false false 1.97 1.97 false false false 2 true true false false 1.91 1.91 false false false 3 true true false false 3.85 3.85 false false false 4 true true false false 3.58 3.58 false false false 5 false false false false 0 0 false false false us-types:perShareItemType decimal The amount of net income or loss for the period per each share of common stock outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 36, 37, 38 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 false 11 Common and potential common shares: 2 us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 12 Weighted average common shares outstanding 2 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic us-gaap true na duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 115400000 115.4 false false false 2 false true false false 116500000 116.5 false false false 3 false true false false 115700000 115.7 false false false 4 false true false false 117400000 117.4 false false false 5 false false false false 0 0 false false false xbrli:sharesItemType shares Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 171 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 40 -Subparagraph a Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 8 false 13 Assumed purchase of common shares for treasury 2 lll_AssumedPurchaseOfCommonSharesForTreasury lll false na duration Assumed purchase of common shares for treasury. false false false false false false false false false false false verboselabel false 1 false true false false -4000000 -4.0 false false false 2 false true false false -3600000 -3.6 false false false 3 false true false false -4200000 -4.2 false false false 4 false true false false -3600000 -3.6 false false false 5 false false false false 0 0 false false false xbrli:sharesItemType shares Assumed purchase of common shares for treasury. No authoritative reference available. false 14 Assumed conversion of the CODES 2 us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities us-gaap true na duration No definition available. false false false false false false false false false false false totallabel false 1 false false false false 0 0   [1] false false false 2 false false false false 0 0   [1] false false false 3 false false false false 0 0   [1] false false false 4 false false false false 0 0   [1] false false false 5 false false false false 0 0 false false false xbrli:sharesItemType shares Debt securities outstanding shall be assumed to have been converted at the beginning of the period (or at time of issuance, if later), and the resulting common shares shall be included in common shares used to calculate diluted earnings per shares. The dilutive effect of convertible debt securities shall be reflected in diluted Earnings Per Share by application of the if-converted method. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number APB14-1 -Paragraph 32 -Subparagraph b false 22 Shares excluded from computation of diluted earnings per share 2 us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 2600000 2.6 false false false 2 false true false false 2800000 2.8 false false false 3 false true false false 2400000 2.4 false false false 4 false true false false 2800000 2.8 false false false 5 false false false false 0 0 false false false xbrli:sharesItemType shares Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 13, 14 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 171 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 40 -Subparagraph c false 23 Assumed exercise of stock options [Member] 0 na true na na No definition available. false true false false false false false false false false false http://l-3com.com/role/earningspercommonsharedetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false false 6 true false false false Assumed exercise of stock options [Member] lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_StockOptionsMember lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 false 7 true false false false Assumed exercise of stock options [Member] lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_StockOptionsMember lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 false 8 true false false false Assumed exercise of stock options [Member] lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_StockOptionsMember lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 false 9 true false false false Assumed exercise of stock options [Member] lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_StockOptionsMember lll_DilutiveSecuritiesIncludedInComputationOfEarningsPerShareAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 na No definition available. 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Such share-based awards shall be considered to be outstanding as of the grant date for purposes of computing diluted earnings per share even though their exercise may be contingent upon vesting. Those share-based awards are included in the diluted Earnings Per Share (EPS) computation even if the employee may not receive (or be able to sell) the stock until some future date. Accordingly, all shares to be issued shall be included in computing diluted EPS if the effect is dilutive. The dilutive effect of share-based compensation arrangements shall be computed using the treasury stock method. If the equity share options or other equity instruments are outstanding for only part of a period, the shares issuable shall be weighted to reflect the portion of the period during which the equity instruments were outstanding. 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Such share-based awards shall be considered to be outstanding as of the grant date for purposes of computing diluted earnings per share even though their exercise may be contingent upon vesting. Those share-based awards are included in the diluted Earnings Per Share (EPS) computation even if the employee may not receive (or be able to sell) the stock until some future date. Accordingly, all shares to be issued shall be included in computing diluted EPS if the effect is dilutive. The dilutive effect of share-based compensation arrangements shall be computed using the treasury stock method. If the equity share options or other equity instruments are outstanding for only part of a period, the shares issuable shall be weighted to reflect the portion of the period during which the equity instruments were outstanding. 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Such share-based awards shall be considered to be outstanding as of the grant date for purposes of computing diluted earnings per share even though their exercise may be contingent upon vesting. Those share-based awards are included in the diluted Earnings Per Share (EPS) computation even if the employee may not receive (or be able to sell) the stock until some future date. Accordingly, all shares to be issued shall be included in computing diluted EPS if the effect is dilutive. The dilutive effect of share-based compensation arrangements shall be computed using the treasury stock method. If the equity share options or other equity instruments are outstanding for only part of a period, the shares issuable shall be weighted to reflect the portion of the period during which the equity instruments were outstanding. 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Such share-based awards shall be considered to be outstanding as of the grant date for purposes of computing diluted earnings per share even though their exercise may be contingent upon vesting. Those share-based awards are included in the diluted Earnings Per Share (EPS) computation even if the employee may not receive (or be able to sell) the stock until some future date. Accordingly, all shares to be issued shall be included in computing diluted EPS if the effect is dilutive. The dilutive effect of share-based compensation arrangements shall be computed using the treasury stock method. If the equity share options or other equity instruments are outstanding for only part of a period, the shares issuable shall be weighted to reflect the portion of the period during which the equity instruments were outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 20 false 1 L-3 Holdings' CODES had no impact on diluted EPS for the quarter or first half periods ended June 25, 2010 or June 26, 2009, because the average market price of L-3 Holdings common stock during these periods was less than the price at which the CODES would have been convertible into L-3 Holdings common stock. As of May 14, 2010 the conversion price was $98.94. 5 31 false NoRounding HundredThousands NoRounding false true