Deposits Deposits-Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Interest Expense, Domestic Deposits
Interest-bearing checking	$ 19	$ 48
Savings and clubs	249	261
Money market savings	540	875
Certificates of deposit	3,256	2,437
Mortgagors deposits	42	40
Interest Expense, Checking, Savings, Money Market Accounts, and CDs	4,106	3,661
Total interest expense	$ 4,106	$ 3,661

Aggregate amount of interest expense on all deposits.

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=114873765&loc=SL114874048-224260

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Amount of interest expense on domestic checking deposit liabilities.

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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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