Employee Benefit Plans - 401 (k) Plan (Details Textual) - 401(k) Plan [Member] - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, matching contribution cost recognized	$ 1.7	$ 1.4	$ 1.5
100% on first 1% [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer matching contributions, percent of one dollar match for employee percentage match	100.00%
50% up to next 5% [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer matching contributions, percent of one dollar match for employee percentage match	50.00%
Defined contribution plan, employer matching contributions, percent of employee's pre-tax contributions	50.00%