Deposits-Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Interest Expense, Domestic Deposits
Interest-bearing checking	$ 29	$ 30
Savings and clubs	256	265
Money market savings	533	466
Certificates of deposit	3,799	4,427
Mortgagors deposits	23	44
Interest Expense, Checking, Savings, Money Market Accounts, and CDs	$ 4,640	$ 5,232

Amount of interest expense on domestic checking deposit liabilities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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- Definition

Interest expense incurred on all money market deposits.

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- Definition

The aggregate interest expense incurred on the following for deposits in domestic offices: (1) transaction accounts (NOW, and telephone and preauthorized transfer accounts), (2) money market deposits and (3) savings deposits.

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- Definition

Interest expense incurred on other deposits in domestic offices.

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Interest expense incurred on all savings account deposits.

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- Definition

The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

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