Allowance for Loan Losses - Allowance for Loan Losses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of the period	$ 16,102	$ 19,565	$ 15,992	$ 18,270
Total loans charged-off	1,097	1,801	1,592	3,259
Total loan recoveries	316	387	921	1,056
Net loans charged-off (recovered)	781	1,414	671	2,203
Total provision charged to operating expense	339	729	339	2,813
Balance at the end of the period	15,660	18,880	15,660	18,880
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	293	825	322	1,242
Total loan recoveries	108	126	498	196
Total provision charged to operating expense	(93)	(940)	119	802
Commercial [Member] | Owner Occupied Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off		6		138
Total loan recoveries	2	14	6	46
Commercial [Member] | Non-owner Occupied Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off		45	22	191
Total loan recoveries	74	1	75	3
Commercial [Member] | Residential Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off
Total loan recoveries
Commercial [Member] | Development & Spec Land Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	166		173
Total loan recoveries
Commercial [Member] | Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	127	774	127	913
Total loan recoveries	32	111	417	147
Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	172	416	194	559
Total loan recoveries	3	5	7	8
Total provision charged to operating expense	(383)	675	(987)	986
Real Estate [Member] | Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	172	416	194	559
Total loan recoveries	3	5	7	8
Real Estate [Member] | Residential Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off
Total loan recoveries
Real Estate [Member] | Mortgage Warehousing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off
Total loan recoveries
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	632	560	1,076	1,458
Total loan recoveries	205	256	416	852
Total provision charged to operating expense	815	994	1,207	1,025
Consumer [Member] | Direct Installment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	44	88	77	195
Total loan recoveries	21	54	39	448
Consumer [Member] | Direct Installment Purchased [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off
Total loan recoveries
Consumer [Member] | Indirect Installment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	341	271	568	624
Total loan recoveries	147	202	266	372
Consumer [Member] | Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans charged-off	247	201	431	639
Total loan recoveries	$ 37		$ 111	$ 32