Loans Receivable and Allowance for Loan Losses - Analysis of Loans Modified in Troubled Debt Restructuring by Type of Concession (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) Loan	Sep. 30, 2015 USD ($) Loan	Sep. 30, 2016 USD ($) Loan	Sep. 30, 2015 USD ($) Loan
Financing Receivable, Modifications [Line Items]
Number of Loans | Loan	10	22	52	132
Recorded Investment | $	$ 533	$ 888	$ 3,927	$ 5,930
Extensions of maturity
Financing Receivable, Modifications [Line Items]
Number of Loans | Loan	0	1	3	1
Recorded Investment | $	$ 0	$ 183	$ 1,995	$ 183
Interest-rate reductions
Financing Receivable, Modifications [Line Items]
Number of Loans | Loan	10	21	49	131
Recorded Investment | $	$ 533	$ 705	$ 1,932	$ 5,747