Loans - Pre-Modification and Post-Modification Outstanding Recorded Investments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014 Contract	Sep. 30, 2013 Contract	Sep. 30, 2014 Contract	Sep. 30, 2013 Contract
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	11	13	34	61
Pre-Modification Outstanding Recorded Investment	$ 12,044	$ 18,442	$ 44,181	$ 48,713
Post-Modification Outstanding Recorded Investment	8,884	18,684	37,179	46,951
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	1	4	9	11
Pre-Modification Outstanding Recorded Investment	3,159	9,685	11,340	20,140
Post-Modification Outstanding Recorded Investment	3,159	8,799	10,361	17,455
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	4	0	12	9
Pre-Modification Outstanding Recorded Investment	6,111	0	22,282	10,304
Post-Modification Outstanding Recorded Investment	2,865	0	18,011	10,219
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	1	2	3	6
Pre-Modification Outstanding Recorded Investment	403	6,402	5,731	10,882
Post-Modification Outstanding Recorded Investment	500	7,836	4,232	12,826
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	5	2	15	15
Pre-Modification Outstanding Recorded Investment	6,514	6,402	28,013	21,186
Post-Modification Outstanding Recorded Investment	3,365	7,836	22,243	23,045
Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	3	6	7	28
Pre-Modification Outstanding Recorded Investment	568	2,307	2,893	6,887
Post-Modification Outstanding Recorded Investment	557	2,001	2,640	5,997
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	2	1	3	7
Pre-Modification Outstanding Recorded Investment	1,803	48	1,935	500
Post-Modification Outstanding Recorded Investment	$ 1,803	$ 48	$ 1,935	$ 454