Employee Benefit Plans (Table Text Block)	3 Months Ended	9 Months Ended
Dec. 31, 2020	Dec. 31, 2020
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Post Retirement Benefit Cost	Quarter Ended December 31, 2020 2019 (Unaudited) (In thousands) Service cost for benefits earned during the period $ 317 $ 292 Other components of net periodic benefit costs: Interest cost on accumulated postretirement benefit 230 241 Other components 17 22 Total other components of net periodic benefit costs 247 263 Net periodic postretirement benefit cost $ 564 $ 555	Nine Months Ended December 31, 2020 2019 (Unaudited) (In thousands) Service cost for benefits earned during the period $ 950 $ 876 Other components of net periodic benefit costs: Interest cost on accumulated postretirement benefit 689 723 Other components 51 67 Total other components of net periodic benefit costs 740 790 Net periodic postretirement benefit cost $ 1,690 $ 1,666

Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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