Loans Receivable and Allowance for Loan Losses - Schedule of Troubled Debt Restructurings Subsequently Defaulted (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 SecurityLoan	Dec. 31, 2013 SecurityLoan
Financing Receivable, Modifications [Line Items]
Number of Loans	0	4
Outstanding Recorded Investment	$ 0	$ 1,945
Commercial Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	3
Outstanding Recorded Investment	0	1,815
Consumer Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	1
Outstanding Recorded Investment	$ 0	$ 130