Pension And Other Postretirement Benefit Plans (Benefit Obligations, Plan Assets, And Funded Status) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value, beginning of year	$ 229,568
Plan assets at fair value, end of year	244,969	$ 229,568
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation				$ 273,370	$ 270,666
Projected benefit obligation	278,189	269,250	$ 269,250	278,189	273,658
Projected benefit obligation, beginning of year	273,658	269,250
Service cost	6,008	5,177	5,382
Interest cost	10,810	10,801	10,441
Effect of discount rate change	5,177	1,209
Foreign currency exchange rate changes	(2,526)	1,268
Other	7,268	781
Benefit payments	(22,206)	(14,828)
Projected benefit obligation, end of year	278,189	273,658	269,250
Plan assets at fair value, beginning of year	229,568	220,151
Actual return on plan assets	9,772	15,902
Employer contributions	29,489	7,891
Foreign currency exchange rate changes	(1,654)	452
Plan assets at fair value, end of year	244,969	229,568	220,151
Funded status of the plans, end of year	(33,220)	(44,090)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	31,635	36,786	36,786	$ 31,635	$ 32,945
Projected benefit obligation, beginning of year	32,945	36,786
Service cost	222	229	247
Interest cost	1,371	1,471	1,535
Effect of discount rate change	563	612
Foreign currency exchange rate changes	(447)	(151)
Other	(126)	(3,212)
Benefit payments	(2,893)	(2,790)
Projected benefit obligation, end of year	31,635	32,945	36,786
Plan assets at fair value, beginning of year	3,467	3,054
Actual return on plan assets	150	105
Employer contributions	2,993	3,098
Foreign currency exchange rate changes	0	0
Plan assets at fair value, end of year	3,717	3,467	$ 3,054
Funded status of the plans, end of year	$ (27,918)	$ (29,478)