Other Financial Data - Other Liabilities (Details) - USD ($) $ in Millions	Sep. 26, 2020	Dec. 31, 2019
Other Liabilities [Abstract]
Defined benefit plans	$ 1,472	$ 1,524
Non-current contract liabilities (Note 2)	266	274
Unrecognized tax benefits	54	53
Deferred income taxes	179	184
Other	255	241
Other liabilities	$ 2,226	$ 2,276

This element represents other noncurrent liabilities other than specified in the taxonomy.

No definition available.

Name:	msi_OtherUnspecifiedNoncurrentLiabilities
Namespace Prefix:	msi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The non-current portion of the gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date, excluding amounts pertaining to examined tax returns.

+ References

No definition available.

+ Details

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan.

+ References

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-Publisher FASB
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+ Details

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Period Type:	instant

- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- References

No definition available.

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