Non-interest Revenue Non-interest Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Noninterest income	$ 1,079	$ 1,139	$ 2,383	$ 2,348
Noninterest income out of scope of ASU 606
Disaggregation of Revenue [Line Items]
Noninterest income	142	134	541	341
Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Noninterest income	937	1,005	1,842	2,007
Depository fees and charges | Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	854	851	1,687	1,746
Loan fees and service charges | Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	67	127	122	225
Other noninterest income | Noninterest income in scope of ASU 606
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	$ 16	$ 27	$ 33	$ 36