Shareholders' Equity - Schedule of Grant Date Fair Value and Stock-based Compensation Expense Allocated (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 20,741	$ 6,499	$ 4,463
Stock Options
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Weighted average, grant date fair value	$ 14.06	$ 11.51	$ 8.54
Restricted Shares (RSAs and RSUs)
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Weighted average, grant date fair value	$ 60.53	$ 49.38	$ 31.90
Total Direct Costs
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 6,999	$ 4,132	$ 2,128
Selling, General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 13,742	$ 2,367	$ 2,335