Distribution of Undisbursed Loan Commitments (Detail)

v2.4.0.6

Distribution of Undisbursed Loan Commitments (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Loss Contingencies [Line Items]
Total Undisbursed Loan Commitments	$ 235,408	$ 196,725
Commitments to Extend Credit [Member]
Loss Contingencies [Line Items]
Total Undisbursed Loan Commitments	205,833	158,748
Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Total Undisbursed Loan Commitments	10,544	12,742
Commercial Letters of Credit [Member]
Loss Contingencies [Line Items]
Total Undisbursed Loan Commitments	5,442	9,298
Unused Credit Card Lines [Member]
Loss Contingencies [Line Items]
Total Undisbursed Loan Commitments	$ 13,588	$ 15,937