Debt Instrument, Early Termination Fee

No definition available.

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Namespace Prefix:	ktos_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument, Escrow Interest

+ References

No definition available.

+ Details

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Namespace Prefix:	ktos_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line Of Credit Facility Fixed Coverage Ratio

+ References

No definition available.

+ Details

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Namespace Prefix:	ktos_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentRepurchaseAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt premium.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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+ Details

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

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reflects the difference between the fair value of payments made to legally extinguish a debt and its carrying value at that time. This item excludes the write-off of amounts previously capitalized as debt issuance costs.

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Balance Type:	credit
Period Type:	duration

- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

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-Publisher FASB
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Balance Type:	debit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
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Balance Type:	debit
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Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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Debt - Issuance of 7.00% Senior Secured Notes due 2019 (Details)				1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 23, 2016 USD ($)	Sep. 22, 2015 USD ($)	May 14, 2014 USD ($)	May 31, 2014 USD ($)	Dec. 31, 2017 USD ($)	Dec. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 25, 2016 USD ($)	Nov. 30, 2017 USD ($)	Sep. 12, 2017 USD ($)	Aug. 21, 2015 USD ($)
Debt Instrument [Line Items]
Principal					$ 300,800,000.0	$ 300,000,000	$ 300,800,000.0
Proceeds from the issuance of long-term debt, net of issuance costs						0	300,000,000	$ 0
Gain (loss) on extinguishment of debt						0	(17,300,000)	200,000
Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement borrowings				$ 41,000,000
Outstanding borrowings						$ 0					$ 41,000,000
Maximum borrowing capacity			$ 110,000,000.0								$ 110,000,000.0
Senior notes \| 7% Senior Notes due 2019
Debt Instrument [Line Items]
Stated interest rate				7.00%		7.00%
Principal				$ 625,000,000.0		$ 300,000,000
Proceeds from the issuance of long-term debt, net of issuance costs			618,500,000
Original issue discount		$ 1,400,000	6,500,000		1,600,000		1,600,000	100,000
Debt issuance costs			$ 8,800,000
Reacquisition price		175,000,000							$ 385,200,000	$ 135,500,000
Write off of unamortized issue costs		1,800,000					2,300,000	100,000
Unamortized premium									$ 12,000,000
Gain (loss) on extinguishment of debt		(3,400,000)			$ (15,200,000)		(17,300,000)	200,000
Fixed charge coverage ratio				2.0
Legal fees		$ 200,000
Debt repurchased and extinguished	$ 14,500,000						435,500,000	14,500,000
Gain (loss) on extinguishment of debt before amortization of issuance cost and discount							$ (13,400,000)	$ 400,000
Senior notes \| 10% Senior Notes due June 2017
Debt Instrument [Line Items]
Stated interest rate				10.00%
Principal				$ 625,000,000.0
Reacquisition price				661,500,000
Early termination fee				31,200,000
Write off of unamortized issue costs				15,500,000
Unamortized premium				12,900,000
Interest accrued in escrow				5,300,000
Gain (loss) on extinguishment of debt				$ (39,100,000)