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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after 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 amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the 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 amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during 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 amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth 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 amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during 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 amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during 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.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, resulting from a business combination.

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The number of businesses acquired by the entity during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Intangible Assets and Goodwill (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		0 Months Ended
	Apr. 04, 2015	Mar. 29, 2014	Nov. 18, 2014	Dec. 31, 2014
Intangible Assets And Goodwill
Amortization expense on intangibles	$ 2us-gaap_AmortizationOfIntangibleAssets	$ 1us-gaap_AmortizationOfIntangibleAssets
Finite-Lived Intangible Assets, Future Amortization Expense
2015	7
2016	7
2017	7
2018	6
2019	5
2020	2
Business Acquisition [Line Items]
Goodwill	390us-gaap_Goodwill			383us-gaap_Goodwill
Acquired Communications Software Provider
Business Acquisition [Line Items]
Payments to acquire businesses, gross			22
Goodwill	7
Identifiable intangible assets recognized, other than goodwill	12
Business Acquisition of Two Public Safety Software-Based Solutions
Business Acquisition [Line Items]
Payments to acquire businesses, gross	50
Number of acquisitions	2
First of Two Acquisition of Public Safety Software-Based Solutions
Business Acquisition [Line Items]
Identifiable intangible assets recognized	5
Other Assets \| Second of Two Acquisition of Public Safety Software-Based Solutions
Business Acquisition [Line Items]
Identifiable intangible assets recognized	$ 44