Employee Benefit Plans (Table Text Block)	3 Months Ended
Jun. 30, 2021
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Post Retirement Benefit Cost	Quarter Ended June 30, 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

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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