Guarantees - Summary (Details) - USD ($) $ in Thousands	9 Months Ended
	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Guarantees [Abstract]
Amounts guaranteed (not to exceed)	$ 119,342	$ 143,298	$ 176,762
Amounts outstanding under guarantee	37,624	103,846	79,336
Fair value of guarantees	1,112	3,714	2,890
Amounts due to local banks on behalf of suppliers and included in accounts payable	$ 0	$ 18,659	$ 0
Number of years before expiring guarantees	1 year