Loans Receivable, Net - Additional Information (Detail) - USD ($)		3 Months Ended		12 Months Ended
	Jul. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans with non-accrual of interest		$ 16,193,000		$ 18,274,000
Financing receivables 90 days past due and still accruing		0
Impaired loans on non-accrual commercial real estate, multi-family, land, construction, commercial and industrial loans		250,000
Impaired loan portfolio total		34,443,000		38,372,000
Allocation in allowance for loan losses		249,000		1,339,000
Average balance of impaired loans		34,600,000	$ 36,300,000
Troubled debt restructuring loans		31,500,000		31,300,000
Troubled debt restructuring loans with accrual interest		26,700,000		26,300,000
Non-accrual loan total troubled debt restructurings		4,800,000		4,900,000
Specific reserves to loans accruing troubled debt restructurings		170,000		262,000
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans with non-accrual of interest		8,788,000		$ 5,779,000
Recorded investment in mortgage and consumer loans collateralized, foreclosure amount		2,800,000
Foreclosed property held		$ 2,000,000
Colonial American Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 0