Loans Receivable and Allowance for Loan Losses - Summary of Impaired Loans Receivable by Class (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	$ 57,962	$ 94,514
Recorded Investment	50,867	85,395
Related Allowance	2,271	7,127
Average Recorded Investment	51,225	87,869
Interest Income Recognized	1,949	2,328
Residential [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	27,141	30,465
Recorded Investment	23,152	25,535
Related Allowance	1,901	2,367
Average Recorded Investment	23,579	26,244
Interest Income Recognized	956	912
Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,240	42,526
Recorded Investment	1,240	41,014
Related Allowance	185	2,329
Average Recorded Investment	1,361	41,387
Interest Income Recognized	63	914
Multi-Family [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Construction [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	2,358	0
Recorded Investment	2,351	0
Related Allowance	0	0
Average Recorded Investment	1,170	0
Interest Income Recognized	16	0
Mortgage Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	30,739	72,991
Recorded Investment	26,743	66,549
Related Allowance	2,086	4,696
Average Recorded Investment	26,110	67,631
Interest Income Recognized	1,035	1,826
Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	24,366	18,708
Recorded Investment	21,756	16,462
Related Allowance	91	2,318
Average Recorded Investment	22,682	17,790
Interest Income Recognized	799	394
Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	2,857	2,815
Recorded Investment	2,368	2,384
Related Allowance	94	113
Average Recorded Investment	2,433	2,448
Interest Income Recognized	115	108
Loans With No Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	39,816	23,881
Recorded Investment	33,376	18,346
Related Allowance	0	0
Average Recorded Investment	33,245	18,544
Interest Income Recognized	1,262	389
Loans With No Related Allowance [Member] | Residential [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	12,144	14,942
Recorded Investment	8,799	10,629
Related Allowance	0	0
Average Recorded Investment	9,079	11,138
Interest Income Recognized	451	357
Loans With No Related Allowance [Member] | Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	4,971
Recorded Investment	0	4,708
Related Allowance	0	0
Average Recorded Investment	0	4,713
Interest Income Recognized	0	0
Loans With No Related Allowance [Member] | Multi-Family [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Loans With No Related Allowance [Member] | Construction [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	2,358	0
Recorded Investment	2,351	0
Related Allowance	0	0
Average Recorded Investment	1,170	0
Interest Income Recognized	16	0
Loans With No Related Allowance [Member] | Mortgage Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	14,502	19,913
Recorded Investment	11,150	15,337
Related Allowance	0	0
Average Recorded Investment	10,249	15,851
Interest Income Recognized	467	357
Loans With No Related Allowance [Member] | Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	23,754	2,718
Recorded Investment	21,144	2,179
Related Allowance	0	0
Average Recorded Investment	21,875	1,823
Interest Income Recognized	747	4
Loans With No Related Allowance [Member] | Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,560	1,250
Recorded Investment	1,082	830
Related Allowance	0	0
Average Recorded Investment	1,121	870
Interest Income Recognized	48	28
Loans With Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	18,146	70,633
Recorded Investment	17,491	67,049
Related Allowance	2,271	7,127
Average Recorded Investment	17,980	69,325
Interest Income Recognized	687	1,939
Loans With Allowance Recorded [Member] | Residential [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	14,997	15,523
Recorded Investment	14,353	14,906
Related Allowance	1,901	2,367
Average Recorded Investment	14,500	15,106
Interest Income Recognized	505	555
Loans With Allowance Recorded [Member] | Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,240	37,555
Recorded Investment	1,240	36,306
Related Allowance	185	2,329
Average Recorded Investment	1,361	36,674
Interest Income Recognized	63	914
Loans With Allowance Recorded [Member] | Multi-Family [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Loans With Allowance Recorded [Member] | Construction [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Loans With Allowance Recorded [Member] | Mortgage Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	16,237	53,078
Recorded Investment	15,593	51,212
Related Allowance	2,086	4,696
Average Recorded Investment	15,861	51,780
Interest Income Recognized	568	1,469
Loans With Allowance Recorded [Member] | Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	612	15,990
Recorded Investment	612	14,283
Related Allowance	91	2,318
Average Recorded Investment	807	15,967
Interest Income Recognized	52	390
Loans With Allowance Recorded [Member] | Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,297	1,565
Recorded Investment	1,286	1,554
Related Allowance	94	113
Average Recorded Investment	1,312	1,578
Interest Income Recognized	$ 67	$ 80