Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Detail) - TDRs That Were Restructured (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 loan	Dec. 31, 2012 loan	Dec. 31, 2011 loan
Financing Receivable, Modifications [Line Items]
Number of Loans	39	17	37
Pre-Modification Recorded Investment	$ 20,343	$ 7,345	$ 38,196
Funds Disbursed	30	0	293
Interest and Escrow Capitalized	63	4	188
Charge-offs	0	295	3,000
Post-Modification Recorded Investment	20,436	7,054	35,677
Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Loans	7	5	10
Pre-Modification Recorded Investment	14,439	3,277	886
Funds Disbursed	0	0	0
Interest and Escrow Capitalized	2	0	7
Charge-offs	0	170	0
Post-Modification Recorded Investment	14,441	3,107	893
Office Retail And Industrial
Financing Receivable, Modifications [Line Items]
Number of Loans	6	2	3
Pre-Modification Recorded Investment	2,275	2,416	3,407
Funds Disbursed	30	0	293
Interest and Escrow Capitalized	0	0	9
Charge-offs	0	0	0
Post-Modification Recorded Investment	2,305	2,416	3,709
Multi Family
Financing Receivable, Modifications [Line Items]
Number of Loans	5		1
Pre-Modification Recorded Investment	1,274		14,107
Funds Disbursed	0		0
Interest and Escrow Capitalized	57		0
Charge-offs	0		3,000
Post-Modification Recorded Investment	1,331		11,107
Construction
Financing Receivable, Modifications [Line Items]
Number of Loans	2		1
Pre-Modification Recorded Investment	508		17,508
Funds Disbursed	0		0
Interest and Escrow Capitalized	0		0
Charge-offs	0		0
Post-Modification Recorded Investment	508		17,508
Other Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans	5	5	1
Pre-Modification Recorded Investment	526	1,070	174
Funds Disbursed	0	0	0
Interest and Escrow Capitalized	0	0	74
Charge-offs	0	125	0
Post-Modification Recorded Investment	526	945	248
Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans	13	1	9
Pre-Modification Recorded Investment	1,189	19	523
Funds Disbursed	0	0	0
Interest and Escrow Capitalized	0	0	15
Charge-offs	0	0	0
Post-Modification Recorded Investment	1,189	19	538
1-4 family mortgages
Financing Receivable, Modifications [Line Items]
Number of Loans	1	4	11
Pre-Modification Recorded Investment	132	563	1,440
Funds Disbursed	0	0	0
Interest and Escrow Capitalized	4	4	79
Charge-offs	0	0	0
Post-Modification Recorded Investment	136	567	1,519
Installment
Financing Receivable, Modifications [Line Items]
Number of Loans			1
Pre-Modification Recorded Investment			151
Funds Disbursed			0
Interest and Escrow Capitalized			4
Charge-offs			0
Post-Modification Recorded Investment			$ 155