Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts 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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Debt - Components of Debt and Reconciliation to Carrying Amount of Current and Long-Term Debt (Detail) - USD ($) $ in Millions	Sep. 23, 2016	Jun. 24, 2016	Mar. 24, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 3,331			$ 3,624
Long-term debt, current and noncurrent
Current portion of long-term debt	(549)			(499)
Carrying amount of long-term debt, excluding current portion	2,782			3,125
Carrying amount of long-term debt	3,331			3,624
L-3 Communications Corporation [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	3,350			3,650
Unamortized discounts	(6)			(8)
Deferred debt issue costs	(13)			(18)
Carrying amount of long-term debt	3,331			3,624
Long-term debt, current and noncurrent
Current portion of long-term debt	(549)			(499)
Carrying amount of long-term debt, excluding current portion	2,782			3,125
Carrying amount of long-term debt	3,331			3,624
L-3 Communications Corporation [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowings under Amended and Restated Revolving Credit Facility
L-3 Communications Corporation [Member] \| 3.95% Senior Notes due 2016 [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	200	$ 200	$ 500	500
L-3 Communications Corporation [Member] \| 1.50% Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	350			350
L-3 Communications Corporation [Member] \| 5.20% Senior Notes due 2019 [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	1,000			1,000
L-3 Communications Corporation [Member] \| 4.75% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	800			800
L-3 Communications Corporation [Member] \| 4.95% Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	650			650
L-3 Communications Corporation [Member] \| 3.95% Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Principal amount of long-term debt	$ 350			$ 350