Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 900	$ 509	$ 617
Charged to costs and expenses	539	1,063	648
Deductions	(651)	(672)	(756)
Balance at end of year	788	900	509
Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	54,260	80,013	77,846
Charged to costs and expenses	3,592	(25,753)	2,167
Deductions	0	0	0
Balance at end of year	$ 57,852	$ 54,260	$ 80,013