Other Financial Data (Accrued Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accrued Liabilities [Abstract]
Deferred revenue	$ 355us-gaap_DeferredRevenueCurrent	$ 359us-gaap_DeferredRevenueCurrent
Compensation	190	315
Billings in excess of costs and earnings	358us-gaap_BillingsInExcessOfCost	295us-gaap_BillingsInExcessOfCost
Tax liabilities	91us-gaap_AccruedIncomeTaxesCurrent	85us-gaap_AccruedIncomeTaxesCurrent
Customer liabilities	55msi_CustomerReserves	52msi_CustomerReserves
Dividend payable	75	79
Other	582us-gaap_OtherAccruedLiabilitiesCurrent	578us-gaap_OtherAccruedLiabilitiesCurrent
Accrued liabilities	$ 1,706us-gaap_AccruedLiabilitiesCurrent	$ 1,763us-gaap_AccruedLiabilitiesCurrent

This element represents the reserves maintained for any liability arising towards customer.

No definition available.

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 35

-Section 45

-Paragraph 3

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-Name Accounting Standards Codification

-Topic 605

-SubTopic 35

-Section 45

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-Name Accounting Standards Codification

-Topic 605

-SubTopic 35

-Section 45

-Paragraph 4

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- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

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-Topic 210

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph a

-Article 7

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-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

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-Name Accounting Standards Codification

-Topic 944

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-Subparagraph (SX 210.9-03.15(5))

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

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-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e7018-107765

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