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Accounting Policies - Schedule of Risk Concentration (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Concentration Risk [Line Items]
Total	$ 912,672	$ 872,094
Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	22.00%	23.00%	22.00%
Credit Concentration Risk
Concentration Risk [Line Items]
Cash and cash equivalents held in excess of deposit insurance, foreign and domestic	$ 887,886	$ 855,721
Largest balance of cash and cash equivalents held with one financial institution, foreign and domestic	$ 396,430	$ 330,551
1st Largest Channel Partner \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	3.00%	4.00%	4.00%
2nd Largest Channel Partner \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	2.00%	2.00%	2.00%
United States \| Credit Concentration Risk
Concentration Risk [Line Items]
Total	$ 582,882	$ 626,433
Foreign \| Credit Concentration Risk
Concentration Risk [Line Items]
Total	$ 329,790	$ 245,661