Employee Benefit Plans (Table Text Block)	3 Months Ended	9 Months Ended
	Dec. 31, 2021	Dec. 31, 2021
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Post Retirement Benefit Cost	Quarter Ended December 31,     2021   2020     (Unaudited)     (In thousands)           Service cost for benefits earned during the period $ 350 $   317 Other components of net periodic benefit costs:         Interest cost on accumulated postretirement benefit   227   230 Other components   53   17 Total other components of net periodic benefit costs   280   247 Net periodic postretirement benefit cost$ 630 $  564	Nine Months Ended December 31,     2021   2020     (Unaudited)     (In thousands)           Service cost for benefits earned during the period $ 1,051 $   950 Other components of net periodic benefit costs:         Interest cost on accumulated postretirement benefit   681   689 Other components   159   51 Total other components of net periodic benefit costs   840   740 Net periodic postretirement benefit cost$ 1,891 $  1,690