Loans Receivable and Allowance for Loan Losses - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2014 TDRs SecurityLoan Borrowers	Mar. 31, 2013	Dec. 31, 2013 TDRs SecurityLoan Borrowers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Principal amount of nonaccrual loans	$ 64,100,000		$ 76,700,000
Loans less than 90 days past due	25,800,000		33,500,000
Impaired loan defined floor limit	1,000,000
Impaired loans number	152		152
Impaired loans	94,626,000		106,370,000
Number of troubled debt restructurings	118		115
Number of borrowers	114		110
Loans and leases receivable, impaired, nonperforming, accrual of interest	57,800,000		58,200,000
Weighted average modified interest rate	4.31%	4.30%
Weighted average prior modification rate	5.23%	5.90%
Allowances for loan losses	7,130,000		10,217,000
Average balance of impaired loans	95,327,000
Impaired Loans - Trouble Debt Restructurings [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Allowances for loan losses	41,000	380,000
With Related Allowance For Loan Losses [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Allowances for loan losses	7,130,000		10,217,000
No Allowance for Loan Losses Required [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired financing receivable with no related allowance	$ 20,480,000		$ 21,958,000