VSE Corporation Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements - Earn-out Obligation Measured on Recurring Basis (Details) - Level 3 - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 36,700	$ 0
Acquisition date fair value of contingent consideration		34,800
Earn-out payments	(31,700)
Fair value adjustment included in costs and operating expenses	(5,000)	1,900
Reclassification from long-term to current	0	0
Ending balance	0	36,700
Other current assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	31,700	0
Acquisition date fair value of contingent consideration		34,800
Earn-out payments	(31,700)
Fair value adjustment included in costs and operating expenses	(5,000)	1,900
Reclassification from long-term to current	5,000	(5,000)
Ending balance	0	31,700
Long-term Portion
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	5,000	0
Acquisition date fair value of contingent consideration		0
Earn-out payments	0
Fair value adjustment included in costs and operating expenses	0	0
Reclassification from long-term to current	(5,000)	5,000
Ending balance	$ 0	$ 5,000