Share-Based Compensation - Unrecognized Compensation Expense (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2019 USD ($)
Unrecognized Share Based Compensation Expense [Line Items]
Unrecognized Expense	$ 146,030
Stock options
Unrecognized Share Based Compensation Expense [Line Items]
Unrecognized Expense	$ 17,537
Average Expected Recognition Period - in Years	2 years 10 months 20 days
Restricted stock units and awards
Unrecognized Share Based Compensation Expense [Line Items]
Unrecognized Expense	$ 128,493
Average Expected Recognition Period - in Years	3 years 1 month 6 days