Significant Customers & Concentration of Credit Risk (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Concentration Risk [Line Items]
Unbilled accounts receivable	$ 87,230		$ 110,575
Single Customer
Concentration Risk [Line Items]
Concentration risk percentage	14.00%
Unbilled accounts receivable	$ 12,500
Single Financial Services Customer
Concentration Risk [Line Items]
Unbilled accounts receivable	$ 10,400
Revenue | Single Customer | Automotive Industry
Concentration Risk [Line Items]
Concentration risk percentage	13.00%	14.00%
Revenue | Single Financial Services Customer | Financial & Insurance Industry [Member]
Concentration Risk [Line Items]
Concentration risk percentage	9.00%	9.00%
Revenue | Automotive Industry
Concentration Risk [Line Items]
Concentration risk percentage	23.00%	25.00%
Revenue | Financial & Insurance Industry [Member]
Concentration Risk [Line Items]
Concentration risk percentage	17.00%	16.00%
Accounts Receivable | Single Financial Services Customer
Concentration Risk [Line Items]
Concentration risk percentage	8.00%