Commitments, Contingencies and Subsequent Events (Details) $ / shares in Units, $ in Thousands								6 Months Ended
	May 05, 2021 USD ($)	Apr. 19, 2021 USD ($) shares	Apr. 06, 2021 USD ($) $ / shares shares	Nov. 23, 2020 USD ($)	Nov. 19, 2020 USD ($) $ / shares shares	Oct. 20, 2020 USD ($)	Sep. 11, 2017 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jul. 30, 2021 employee	Dec. 31, 2020 USD ($)
Subsidiary, Sale of Stock [Line Items]
Payments for repurchase of common stock								$ 1,251	$ 0
Proceeds from issuance of common stock			$ 64,300					64,269	0
Payments for repurchase of warrants								26,894	$ 0
Working capital								$ 139,700			$ 105,200
Exchangeable Redeemable Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Conversion of preferred stock to common stock				$ 108,900	$ 108,900
IPO
Subsidiary, Sale of Stock [Line Items]
Number of shares issued (in shares) | shares					17,200,000
Share price (in dollars per share) | $ / shares					$ 17.00
Net proceeds from initial public offering					$ 272,800
Repayments of debt					21,000
IPO | Exchangeable Redeemable Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Conversion of preferred stock to common stock					108,900
IPO | Class B Common Stock | Telos ID
Subsidiary, Sale of Stock [Line Items]
Payments for repurchase of common stock					$ 30,000
Secondary Public Offering
Subsidiary, Sale of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares) | shares			9,100,000
Sale of stock, price per share (in dollars per share) | $ / shares			$ 33.00
Sale of stock, number of shares issued by certain existing shareholders (in shares) | shares			7,000,000.0
Proceeds from issuance of common stock			$ 64,300
Subsequent Event
Subsidiary, Sale of Stock [Line Items]
Number of employees hired | employee										7
Hamot
Subsidiary, Sale of Stock [Line Items]
Litigation settlement, amount awarded from other party							$ 278
Legal fees						$ 2,540
Litigation settlement, amount awarded to other party	$ 1,000
Enlightenment Capital Solutions Fund, II L.P.
Subsidiary, Sale of Stock [Line Items]
Payments for repurchase of common stock		$ 1,300
Stock repurchased during period (in shares) | shares		39,682
Payments for repurchase of warrants		$ 26,900
Warrants repurchased during period (in shares) | shares		900,970