Employee Retirement Plans (Expected Return on Plan Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Interest cost	$ 525	$ 577	$ 1,050	$ 1,154
Expected return on assets	(647)	(721)	(1,294)	(1,442)
Net periodic benefit income	$ (122)	$ (144)	$ (244)	$ (288)