Fair Value of Financial Instruments - Carrying Amounts and Estimated Fair Values of Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Assets:
Cash and due from banks		$ 20,737	$ 19,645
Interest-earning bank balances		108,155	114,563
Restricted cash		1,000	5,000
Investment securities available for sale		299,502	295,686
Investment securities held-to-maturity		250	250
Restricted equity investments		15,806	15,791
Liabilities:
Savings deposits		244,405	241,754
Advances from FHLBNY		85,367	85,416
Junior subordinated debentures		92,786	92,786
Carrying Amount [Member]
Assets:
Cash and due from banks		20,737	19,645
Interest-earning bank balances		108,155	114,563
Restricted cash		1,000	5,000
Investment securities available for sale		299,502	295,686
Investment securities held-to-maturity		250	250
Loans receivable, net		1,593,198	1,592,743
Hedged commercial loans	[1]	1,561	1,634
Restricted equity investments		15,806	15,791
Liabilities:
Demand deposits		1,079,666	1,095,012
Savings deposits		244,405	241,754
Time deposits		409,917	404,597
Advances from FHLBNY		85,367	85,416
Junior subordinated debentures		92,786	92,786
Fair value interest rate swaps		146	165
Carrying Amount [Member] | Interest Rate Swaps [Member]
Assets:
Interest rate swaps		1,671	2,077
Liabilities:
Interest rate swaps		1,679	2,087
Estimated Fair Value [Member]
Assets:
Cash and due from banks		20,737	19,645
Interest-earning bank balances		108,155	114,563
Restricted cash		1,000	5,000
Investment securities available for sale		299,502	295,686
Investment securities held-to-maturity		250	250
Loans receivable, net		1,576,654	1,575,818
Hedged commercial loans	[1]	1,561	1,634
Restricted equity investments		15,806	15,791
Liabilities:
Demand deposits		1,050,609	1,070,680
Savings deposits		236,876	235,216
Time deposits		416,972	412,903
Advances from FHLBNY		85,866	85,703
Junior subordinated debentures		64,478	64,282
Fair value interest rate swaps		146	165
Estimated Fair Value [Member] | Interest Rate Swaps [Member]
Assets:
Interest rate swaps		1,671	2,077
Liabilities:
Interest rate swaps		$ 1,679	$ 2,087

[1] Includes positive market value adjustment of $146 thousand and $165 thousand at March 31, 2017 and December 31, 2016, respectively, which is equal to the change in value of related interest rate swaps designated as fair value hedges of these hedged loans in accordance with FASB ASC 815.