Business Acquisition Percentage Of Acquired Stock

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Capacity of Power Plant

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Early Repayment of Debt, Principal

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- Definition

Early Termination Fees

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- Definition

Fuel Supply Agreement, Term

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Number of Debt Instruments

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- Definition

Percentage of Ownership

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- Definition

Percentage of Power to be Purchased

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- Definition

Proceeds from Government Grant

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- Definition

Term of Agreement

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Face (par) amount of debt instrument at time of issuance.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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-Glossary Deferred Tax Asset

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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-Glossary Financing Activities

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Acquisitions - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended			0 Months Ended		3 Months Ended
Acquisitions - Additional Information (Detail) (USD $)	Jul. 31, 2014	Nov. 01, 2013	Jan. 30, 2015	Jan. 31, 2014	Jan. 31, 2013	Oct. 11, 2013	Dec. 16, 2013	Jan. 30, 2015
Business Acquisition [Line Items]
Receivable due from Plainfield			$ 896,000,000us-gaap_AccountsReceivableNetCurrent	$ 1,082,000,000us-gaap_AccountsReceivableNetCurrent				$ 896,000,000us-gaap_AccountsReceivableNetCurrent
Interest expense			75,000,000us-gaap_InterestExpense	82,000,000us-gaap_InterestExpense	93,000,000us-gaap_InterestExpense
Loss recorded as bad debt		42,000,000us-gaap_ProvisionForDoubtfulAccounts	5,000,000us-gaap_ProvisionForDoubtfulAccounts	44,000,000us-gaap_ProvisionForDoubtfulAccounts	2,000,000us-gaap_ProvisionForDoubtfulAccounts
Proceeds from U.S. Treasury cash grant	80,000,000ldos_ProceedsfromGovernmentGrant		80,000,000ldos_ProceedsfromGovernmentGrant	0ldos_ProceedsfromGovernmentGrant	0ldos_ProceedsfromGovernmentGrant
Deferred tax assets	27,000,000us-gaap_DeferredTaxAssetsGross		311,000,000us-gaap_DeferredTaxAssetsGross	241,000,000us-gaap_DeferredTaxAssetsGross				311,000,000us-gaap_DeferredTaxAssetsGross
Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Percentage of ownership						100.00%
Capacity of power plant						37.5
Contingent consideration						6,000,000
maxIT Healthcare Holdings, Inc.
Business Acquisition [Line Items]
Percent of acquired stock			100.00%					100.00%
Connecticut Light and Power \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Percentage of power to be purchased						80.00%
Term of agreement						15 years
Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Receivable due from Plainfield						137,000,000
Carlyle Group \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Repayment of principal							152,000,000
Repayment of debt							165,000,000
Interest expense							7,000,000
Early termination fees							6,000,000
Secured Debt \| Carlyle Group \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Number of debt instruments financed by Carlyle Grp						2
Senior notes, face amount						148,000,000
Receivable from PRE Holdings \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Loss recorded as bad debt		32,000,000
Minimum \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Fuel supply agreement, term						5 years
Maximum \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Fuel supply agreement, term						15 years
November 2015 or the successful sale of the plant \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Contingent consideration			2,000,000					2,000,000
Achievement of Milestones \| Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Contingent consideration			3,000,000					3,000,000
Plainfield Renewal Energy Holdings LLC
Business Acquisition [Line Items]
Asset impairment charges								$ 40,000,000