Derivatives (Table Text Block)	6 Months Ended
Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative instruments in statement of financial position, fair value	Derivatives Fair Values as of September 30, 2021 March 31, 2021 (Unaudited) (In thousands) Interest rate contracts designated as hedging instruments: Assets $ – $ – Liabilities $ 3,292 $ 5,141 Notional amount$ 235,000 $ 235,000
Effect of Interest Rate Contracts on the Statement of Operations	The Effect of Interest Rate Contracts on the Statements of Operations for the Quarters Ended September 30, 2021 September 30, 2020 (Unaudited) (In thousands) (Gain) loss recognized in AOCI on interest rate contracts $ (929) $ (1,007) (Gain) loss reclassified from AOCI into income$( 1,003 )$( 961 )

Tabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4E
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624181-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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