Revenue Recognition - Disaggregated Revenue (Details) - Tech-Focused [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Disaggregated revenue	$ 33,784	$ 37,359	$ 70,417	$ 74,479
Dice [Member]
Disaggregation of Revenue [Line Items]
Disaggregated revenue	20,489	23,215	42,974	46,361
ClearanceJobs [Member]
Disaggregation of Revenue [Line Items]
Disaggregated revenue	7,107	6,014	14,007	11,796
eFinancial Careers [Member]
Disaggregation of Revenue [Line Items]
Disaggregated revenue	$ 6,188	$ 8,130	$ 13,436	$ 16,322