Employee Benefit Plans (Table Text Block)	3 Months Ended	6 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Post Retirement Benefit Cost	Quarter Ended September 30, 2020 2019 (Unaudited) (In thousands) Service cost for benefits earned during the period $ 316 $ 292 Other components of net periodic benefit costs: Interest cost on accumulated postretirement benefit 229 241 Other components 17 23 Total other components of net periodic benefit costs 246 264 Net periodic postretirement benefit cost $ 562 $ 556	Six Months Ended September 30, 2020 2019 (Unaudited) (In thousands) Service cost for benefits earned during the period $ 633 $ 584 Other components of net periodic benefit costs: Interest cost on accumulated postretirement benefit 459 482 Other components 34 45 Total other components of net periodic benefit costs 493 527 Net periodic postretirement benefit cost $ 1,126 $ 1,111

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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