Company Matching Contributions In Parent Common Stock And Cash.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

+ Details

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- Definition

The ultimate trend rate for health care costs.

+ References

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Pensions and Other Employee Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Aggregate accumulated benefit obligation (ABO)	$ 3,272	$ 2,657
Pension Plans [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to plans in 2015	100
Pension Plans [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to plans in 2015	132
U.S. Based Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend in 2015	7.50%
U.S. Based Pension Plans [Member] \| 2020 and Thereafter [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend	5.00%
Canadian Based Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend in 2015	7.00%
Canadian Based Pension Plans [Member] \| 2023 and Thereafter [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend	5.00%
Continuing Operations [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's matching contributions in L-3 Holdings' common stock and cash	135	120	126
Discontinued Operations [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's matching contributions in L-3 Holdings' common stock and cash			8
Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to plans in 2015	$ 10