Income Taxes - Provision for income taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income before income tax expense based on the geographic location
United States									$ 25,528	$ 9,454	$ (31,526)
Foreign									23,133	28,710	73,362
Income before income tax expense	$ 2,623	$ 23,201	$ 12,078	$ 10,759	$ 13,110	$ 23,197	$ 1,558	$ 299	48,661	38,164	41,836
Current provision:
Federal									(736)	672	18,747
State									995	447	(108)
Foreign									(2,133)	21,124	24,195
Total current provision									(1,874)	22,243	42,834
Deferred (benefit) provision:
Federal									(3,135)	(315)	(1,289)
State									1,692	1,105	(2,726)
Foreign									3,626	(2,560)	(5,931)
Total deferred (benefit) provision									2,183	(1,770)	(9,946)
Total provision for income taxes	$ (19,623)	$ 10,363	$ 4,830	$ 4,739	$ 4,611	$ 10,400	$ (402)	$ 5,864	$ 309	$ 20,473	$ 32,888