Allocated Share-based Compensation Expense, Additional, Unvested Awards

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- Definition

Allocated Share-based Compensation Expense, Additional, Vested Awards

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Maximum Percentage That Will Ultimately Vest for Shares Provided Under Long Term Performance Based Incentive Equity Awards Based on Target Amount Stated in Agreement

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- Definition

Percentage Of Market Price During Non Compensatory Period

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- Definition

Percentage Of Market Price of Shares For Stock Purchase Program

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- Definition

Percentage Of Stock Awards Vest Or Exercisable

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Percentage Of Stock Awards Vest Or Exercisable After Four Years

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Percentage Of Stock Awards Vest Or Exercisable After Three Years

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Percentage Of Stock Compensation Plans Awards Vest After Certain Date

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Period Of Exercise Of Vested Options After Participants Death Or Disability

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Stock Price

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value, Modification

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- Definition

Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Excluding Dividends Equivalents, Weighted Average Grant Date Fair Value

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- Definition

Stock Awards Exercisable Period

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Stock Conversion Upon Divestiture

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

Aggregate number of common shares reserved for future issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Name Accounting Standards Codification
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
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-Section D
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Stock-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Millions		4 Months Ended	8 Months Ended	11 Months Ended	12 Months Ended
	Sep. 27, 2013 USD ($) $ / shares	Jan. 31, 2014	Sep. 27, 2013 shares	Jan. 01, 2016 USD ($) $ / shares shares	Jan. 30, 2015 USD ($) $ / shares shares	Jan. 31, 2014 USD ($)	Jan. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		4 years 9 months 18 days	5 years	4 years 8 months 12 days	4 years 8 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period \| shares			900,000	800,000	1,000,000
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options				$ 1
Stock exchanged at fair value upon exercises of stock options				3		$ 1
Fair value of vesting awards that vested				29	$ 34	$ 49
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, net of estimated forfeitures				$ 4
Expected weighted-average period of recognition, years				2 years 4 months 24 days
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)				10 years
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)				3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period \| shares				0	100,000
Maximum percentage that will ultimately be awarded				150.00%
Weighted average grant date fair value of the awards granted, excluding dividend equivalents (per share) \| $ / shares				$ 43.78	$ 36.88
Weighted average grant-date fair value, Awards granted (in dollars per share) \| $ / shares				$ 42.61
Vesting Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, net of estimated forfeitures				$ 31
Expected weighted-average period of recognition, years				2 years
2006 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of exercise of vested options after participants death or disability (in months)				18 months
Stock awards exercisable period (in months)				P6M
Percentage of stock awards vest or exercisable after three years		20.00%				20.00%
Percentage of stock awards vest or exercisable after four years		40.00%				40.00%
Percentage of stock awards vest or exercisable, every year				25.00%
Vesting period (in years)				4 years
Stock reserved for future issuance \| shares				4,700,000
Percentage of stock compensation plans awards that vest after January 1, 2006				100.00%
2006 Equity Incentive Plan \| Outside Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)				1 year
2006 Equity Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)				4 years
Expected term (in years)				7 years			5 years
2006 Equity Incentive Plan \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, net of estimated forfeitures				$ 6
Expected weighted-average period of recognition, years				1 year 9 months 18 days
Fair value of vesting awards that vested					$ 2	$ 2
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of market price per share for stock purchase program				15.00%
Percentage of market price for employee purchase program for stock purchases during non-compensatory period				5.00%
Shares authorized and reserved for future issuance under the ESPP \| shares				13,800,000.0
SAIC Adjustment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued to Leidos shareholder upon divestiture of SAIC, ratio	1.4523		1.4523
Increase of expense related to the modification	$ 3
Additional incremental fair value	3
Stock based compensation from discontinued operations	$ 6
Weighted average modification fair value (per share) \| $ / shares	$ 1.02
Group One [Member] \| 2006 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)				4 years