SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Detail Textuals 1) - USD ($)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Feb. 17, 2017
Summary Of Significant Accounting Policies [Line Items]
Assets Held-in-trust	$ 484,300,000	$ 425,900,000
Early adoption of ASU 2018-02
Summary Of Significant Accounting Policies [Line Items]
Early adoption of reclassification of tax effects from AOCI to retained earnings	$ 342,000
Core Deposit Intangibles
Summary Of Significant Accounting Policies [Line Items]
Estimated amortized period of Core Deposit Intangibles	10 years
Core Deposit Intangibles, gross	$ 1,360,000	1,360,000
Accumulated amortization	260,000	$ 27,000
Estimated amortization expense of Core Deposit Intangibles for fiscal years ended March 31, 2019	183,000
Estimated amortization expense of Core Deposit Intangibles for fiscal years ended March 31, 2020	160,000
Estimated amortization expense of Core Deposit Intangibles for fiscal years ended March 31, 2021	140,000
Estimated amortization expense of Core Deposit Intangibles for fiscal years ended March 31, 2022	125,000
Estimated amortization expense of Core Deposit Intangibles for fiscal years ended March 31, 2023	116,000
Estimated amortization expense of Core Deposit Intangibles, thereafter	$ 379,000
Building and improvements
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	up to 45 years
Furniture and equipment
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	three to twenty years
Leasehold improvements
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	fifteen to twenty-five years, or estimated lease term if shorter
Estimated Fair Value | Merchants Bancorp
Summary Of Significant Accounting Policies [Line Items]
CDI			$ 1,363,000