Debt - Components of Debt and Reconciliation to Carrying Amount of Current and Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 25, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 3,626	$ 3,624
Long-term debt, current and noncurrent
Current portion of long-term debt	(499)	(499)
Carrying amount of long-term debt, excluding current portion	3,127	3,125
Carrying amount of long-term debt	3,626	3,624
L-3 Communications Corporation [Member]
Debt Instrument [Line Items]
3.95% Senior Notes due 2016	500	500
1.50% Senior Notes due 2017	350	350
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
3.95% Senior Notes due 2024	350	350
Long-term debt, current and noncurrent
Current portion of long-term debt	(499)	(499)
Carrying amount of long-term debt, excluding current portion	$ 3,127	$ 3,125
L-3 Communications Corporation [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowings under Amended and Restated Revolving Credit Facility
L-3 Communications Holdings, Inc. [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	$ 3,650	$ 3,650
Unamortized discounts	(7)	(8)
Deferred debt issue costs	(17)	(18)
Carrying amount of long-term debt	3,626	3,624
Long-term debt, current and noncurrent
Current portion of long-term debt	(499)	(499)
Carrying amount of long-term debt, excluding current portion	3,127	3,125
Carrying amount of long-term debt	$ 3,626	$ 3,624

Long Term Debt Maturities Repayments Of Principal In Year Seven

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Long Term Debt Maturities Repayments Of Principal In Year Six

+ References

No definition available.

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- Definition

Amount of long-term debt maturing in year ten following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

+ References

No definition available.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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No definition available.

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