Loans Receivable and Allowance for Loan Losses - Schedule of Summarized Loans Receivable (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Servicing Liability at Amortized Cost [Line Items]
Total mortgage loans	$ 3,721,099	$ 3,686,862
Total gross loans	5,259,679	5,196,663
Premiums on purchased loans	4,187	4,202
Unearned discounts	(57)	(62)
Net deferred fees	(6,035)	(5,990)
Loans receivable	5,257,774	5,194,813
Residential [Member]
Servicing Liability at Amortized Cost [Line Items]
Total mortgage loans	1,165,196	1,174,043
Commercial [Member]
Servicing Liability at Amortized Cost [Line Items]
Total mortgage loans	1,404,466	1,400,624
Multi-Family [Member]
Servicing Liability at Amortized Cost [Line Items]
Total mortgage loans	939,018	928,906
Construction [Member]
Servicing Liability at Amortized Cost [Line Items]
Total mortgage loans	212,419	183,289
Commercial Loans [Member]
Servicing Liability at Amortized Cost [Line Items]
Total gross loans	966,444	932,199
Consumer Loans [Member]
Servicing Liability at Amortized Cost [Line Items]
Total gross loans	$ 572,136	$ 577,602