Non-interest Revenue and Expense Non-interest Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Noninterest income	$ 1,198	$ 1,079	$ 2,158	$ 2,383
Noninterest income out of scope of ASU 606
Disaggregation of Revenue [Line Items]
Noninterest income	303	142	370	541
Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Noninterest income	895	937	1,788	1,842
Depository fees and charges \| Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	811	854	1,615	1,687
Loan fees and service charges \| Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	70	67	146	122
Other noninterest income \| Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	$ 14	$ 16	$ 27	$ 33

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

+ References

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 210.9-04.13)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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