Summary of Significant Accounting Policies - Components of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 189,931	$ 253,695
OCI, gain (loss)	(215)	(455)
Ending balance	175,499	233,408
Accumulated effect of currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	12	988
OCI, gain (loss)	(215)	(720)
Ending balance	(203)	268
Accumulated defined benefit plans adjustment attributable to parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	453	259
Ending balance	453	259
Accumulated effect interest rate swap agreement
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	(84)
OCI, gain (loss)	0	265
Ending balance	$ 0	$ 181