Capital Gain on Assets

No definition available.

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- Definition

Capital Loss on Investment in Stock of Subsidiary

+ References

No definition available.

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- Definition

Deferred Tax Assets Capital Loss Carryforwards Due to Conversion of Subsidiary from Corporation to LLC

+ References

No definition available.

+ Details

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- Definition

Income Tax Expense Benefit Due to Conversion of Subsidiary to LLC from Corporation

+ References

No definition available.

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- Definition

Income Tax Reconciliation Uncertain Tax Liability

+ References

No definition available.

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- Definition

Liability For Uncertain Tax Positions

+ References

No definition available.

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- Definition

Ordinary Gain Recognized

+ References

No definition available.

+ Details

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- Definition

Tax Adjustments, Settlements, and Unusual Provisions, Dividend Paid to Employee of the New Company

+ References

No definition available.

+ Details

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- Definition

Tax Adjustments, Settlements, and Unusual Provisions, Special Dividend

+ References

No definition available.

+ Details

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- Definition

Unrecognized tax benefits increases resulting from prior period tax positions and settlements with tax authorities.

+ References

No definition available.

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Topic 350

-SubTopic 20

-Section 50

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-Subparagraph (b)

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-SubTopic 20

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-Subparagraph (e)

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- Definition

The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.24)

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- Definition

The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 15

-Subparagraph (d)

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- Definition

Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

+ References

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

-Publisher FASB

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-Topic 740

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 3

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-Glossary Carryforwards

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- Definition

Amount of deferred tax asset, before valuation allowance, attributable to deductible other tax carryforwards.

+ References

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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-Publisher FASB

-Name Accounting Standards Codification

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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Aug. 01, 2014	Jan. 30, 2015	Jan. 31, 2014	Jan. 31, 2013
Income Taxes [Line Items]
Goodwill impairment charges	$ 486us-gaap_GoodwillImpairmentLoss	$ 486us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss
Capital loss on investment in stock		160
Capital gain on assets		58ldos_CapitalGainonAssets
Capital loss carryover		102
Valuation allowance on the deferred tax asset related to the capital loss carryforward		102
Ordinary gain recognized		34ldos_OrdinaryGainRecognized
Decrease in unrecognized tax benefits due to resolutions with tax authorities		(7)
CityTime uncertain tax liability		0	0	96
Tax benefit from dividend paid to New SAIC's employees		7
Tax benefit from special dividend paid by the company		11
Tax benefit due to conversion of subsidiary to LLC from Partnership		18
Reversal of accruals for unrecognized tax benefits		11	2	2
Unrecognized tax benefits accrued interest and penalties		2	2
Liabilities for uncertain tax positions		19ldos_LiabilityForUncertainTaxPositions	16ldos_LiabilityForUncertainTaxPositions
Liabilities for uncertain tax positions, long-term		6	12
Amount of reasonably possible resolution of reviews		14
Capital Loss Carryforward [Member]
Income Taxes [Line Items]
State tax credit carryforwards		292
State
Income Taxes [Line Items]
State tax credit carryforwards		12
State tax credits		$ 8