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- Definition

Related Party Transaction, Number Of Related Parties

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- Definition

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

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-Name Accounting Standards Codification
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- Definition

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

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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- Definition

The amount for notes payable (written promise to pay), due to related parties.

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- Definition

Amount paid to managing member or general partner, affiliate of managing member or general partner, or affiliate of limited liability company (LLC) or limited partnership (LP) for administrative services provided to the LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

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Amount paid to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

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- Definition

Amount of transactions with related party during the financial reporting period.

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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- 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.

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- Definition

The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

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Related Party Transactions (Details)	3 Months Ended		12 Months Ended
Related Party Transactions (Details)	Mar. 30, 2018 USD ($) related-party	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) related-party	Nov. 30, 2010 USD ($)
Vencore
Related Party Transaction [Line Items]
Repayments of related party debt				$ 3,000,000	$ 500,000
Vencore \| Management Fee
Related Party Transaction [Line Items]
Amount of transaction with related party	$ 2,000,000				3,500,000
Amount of transaction with related party as a percentage of EBITDA	3.00%
Expenses from transactions with related party			$ 3,400,000	3,700,000	3,500,000
Payment for management fee				2,000,000
Vencore \| Advisory Fees
Related Party Transaction [Line Items]
Payment for administrative fees					$ 40,000
Number of related parties in a related party transaction \| related-party					2
Vencore \| 11.5% Senior Subordinated Notes
Related Party Transaction [Line Items]
Number of related parties in a related party transaction \| related-party	2
Vencore \| Contract Labor Services
Related Party Transaction [Line Items]
Payment for administrative fees			0	100,000	$ 200,000
Vencore \| 11.5% Senior Subordinated Notes \| Senior Subordinated Notes
Related Party Transaction [Line Items]
Principal amount						$ 175,000,000.0
Interest Rate						11.50%
Vencore \| Chertoff Group \| Advisory Fees
Related Party Transaction [Line Items]
Payment for administrative fees					20,000
Vencore \| JKH Consulting \| Advisory Fees
Related Party Transaction [Line Items]
Payment for administrative fees					20,000
KeyPoint
Related Party Transaction [Line Items]
Repayments of related party debt	$ 0		2,500,000
Term loan from related parties			215,000,000
KeyPoint \| Advisory Fees
Related Party Transaction [Line Items]
Expenses from transactions with related party			1,000,000	1,000,000
TCW, Crescent Mezzanine, LLC \| The SI Organization Holdings LLC
Related Party Transaction [Line Items]
Ownership interest	3.00%
IP III Mezzanine Partners, L.P. and UT Mezz Partners, L.P \| The SI Organization Holdings LLC
Related Party Transaction [Line Items]
Ownership interest	1.00%
Vencore Holding Corp. and KGS Holding Corp. \| Board Of Managers Service Fee
Related Party Transaction [Line Items]
Payment for administrative fees	$ 0	$ 12,500	$ 42,500	$ 22,500	$ 37,000