Income Taxes - Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Expected future taxable income to fully realize the deferred tax assets	$ 126,386
Change in net deferred tax assets attributable to other comprehensive income	400
Domestic taxable income	(56,305)	$ 50,947	$ 125,289
Unremitted earnings of non-US subsidiaries	505,124
Non-US subsidiary cash and cash equivalents	$ 265,773
Minimum percentage used to measure tax benefit of uncertain tax position	50.00%
Reconciliation of the beginning and ending amounts of total unrecognized tax benefits
Balance at the beginning of the period	$ 8,695	4,667
Gross increase related to current year tax positions	1,878	2,332
Gross increase related to prior year tax positions	1,154	2,059
Settlements		(363)
Balance at the end of the period	11,727	8,695	$ 4,667
Unrecognized tax benefits that would impact effective tax rate	2,691
Accrued interest on income tax contingencies	2,990	$ 1,842
Significant change in unrecognized tax benefits is reasonably possible	$ 856