Total number of share held by related party.

No definition available.

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- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from a long-term borrowing made from related parties 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: Proceeds from Advances from Affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

+ Details

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

- 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

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

- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=tls_TelosCorporationMember
Namespace Prefix:
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Balance Type:
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Certain Relationships and Related Transactions (Details) - USD ($) $ in Thousands				12 Months Ended
	Apr. 18, 2017	Apr. 17, 2017	Mar. 31, 2015	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Emmett Wood
Related Party Transaction [Line Items]
Related party transaction, amounts of transaction				$ 492	$ 1,238	$ 529
Number of shares held by related party (in shares)				73,562	682,502
Director
Related Party Transaction [Line Items]
Related party transaction, amounts of transaction				$ 282	$ 270	270
Porter \| Subordinated Loan Agreements and Promissory Notes \| Affiliated Entity
Related Party Transaction [Line Items]
Proceeds from related party, debt			$ 2,500
Related party transaction, rate	6.00%	12.00%	12.00%
Interest expense, related party					$ 319	$ 330
Porter \| Subordinated Loan Agreements and Promissory Notes \| Telos Corporation \| Affiliated Entity
Related Party Transaction [Line Items]
Noncontrolling interest, ownership percentage by noncontrolling owners			35.00%