Employee Benefit Plans (Table Text Block)	3 Months Ended	6 Months Ended
Sep. 30, 2021	Sep. 30, 2021
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Post Retirement Benefit Cost	Quarter Ended September 30, 2021 2020 (Unaudited) (In thousands) Service cost for benefits earned during the period $ 351 $ 316 Other components of net periodic benefit costs: Interest cost on accumulated postretirement benefit 227 229 Other components 53 17 Total other components of net periodic benefit costs 280 246 Net periodic postretirement benefit cost$ 631 $ 562	Six Months Ended September 30, 2021 2020 (Unaudited) (In thousands) Service cost for benefits earned during the period $ 701 $ 633 Other components of net periodic benefit costs: Interest cost on accumulated postretirement benefit 454 459 Other components 106 34 Total other components of net periodic benefit costs 560 493 Net periodic postretirement benefit cost$ 1,261 $ 1,126

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=123447040&loc=d3e1928-114920

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