Loans and Leases (Schedule of Modifications for Troubled Debt Restructurings) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013 Loans		Jun. 30, 2012 Loans		Jun. 30, 2013 Loans		Jun. 30, 2012 Loans
Financing Receivable Modifications [Line Items]
Number Of Loans	131		9		305		24
Pre-Modification Recorded Investment	$ 7,187		$ 1,698		$ 25,069		$ 16,110
Post-Modification Recorded Investment	7,187		1,698		25,069		16,110
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	56	[2]	2	[2]	(268)	[2]	8	[2]
Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	24		0		63		4
Recorded Investment Subsequently Defaulted	7,196		0		9,380		2,247
Originated Loans And Leases [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	121		5		287		12
Pre-Modification Recorded Investment	6,458		473		22,607		3,013
Post-Modification Recorded Investment	6,458		473		22,607		3,013
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	56	[2]	1	[2]	(225)	[2]	(74)	[2]
Originated Loans And Leases [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	22		0		58		3
Recorded Investment Subsequently Defaulted	6,859		0		8,843		1,339
Purchased Loans And Leases [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	10		4		18		12
Pre-Modification Recorded Investment	729		1,225		2,462		13,097
Post-Modification Recorded Investment	729		1,225		2,462		13,097
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	0	[2]	1	[2]	(43)	[2]	82	[2]
Purchased Loans And Leases [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	2		0		5		1
Recorded Investment Subsequently Defaulted	337		0		537		908
Commercial, Financial, And Agricultural [Member] | Combination Of Modification Types [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	1		0		1		0
Pre-Modification Recorded Investment	241		0		241		0
Post-Modification Recorded Investment	241		0		241		0
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	0	[2]	0	[2]	0	[2]	0	[2]
Commercial, Financial, And Agricultural [Member] | Others [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	11	[3]	1	[3]	23	[3]	2	[3]
Pre-Modification Recorded Investment	1,041	[3]	22	[3]	8,534	[3]	332	[3]
Post-Modification Recorded Investment	1,041	[3]	22	[3]	8,534	[3]	332	[3]
Financial Effect Of Modification On Recorded Investment	0	[1],[3]	0	[1],[3]	0	[1],[3]	0	[1],[3]
Financial Effect Of Modification On Interest	0	[2],[3]	0	[2],[3]	0	[2],[3]	0	[2],[3]
Commercial, Financial, And Agricultural [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	5		0		12		0
Recorded Investment Subsequently Defaulted	6,621		0		7,301		0
Real Estate - Construction [Member] | Combination Of Modification Types [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	0		0		0		0
Pre-Modification Recorded Investment	0		0		0		0
Post-Modification Recorded Investment	0		0		0		0
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	0	[2]	0	[2]	0	[2]	0	[2]
Real Estate - Construction [Member] | Others [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	1	[3]	0	[3]	2	[3]	0	[3]
Pre-Modification Recorded Investment	117	[3]	0	[3]	137	[3]	0	[3]
Post-Modification Recorded Investment	117	[3]	0	[3]	137	[3]	0	[3]
Financial Effect Of Modification On Recorded Investment	0	[1],[3]	0	[1],[3]	0	[1],[3]	0	[1],[3]
Financial Effect Of Modification On Interest	0	[2],[3]	0	[2],[3]	0	[2],[3]	0	[2],[3]
Real Estate - Construction [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	0		0		2		1
Recorded Investment Subsequently Defaulted	0		0		137		908
Real Estate Secured - Residential [Member] | Combination Of Modification Types [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	10		8		17		16
Pre-Modification Recorded Investment	1,186		1,676		2,502		4,110
Post-Modification Recorded Investment	1,186		1,676		2,502		4,110
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	56	[2]	2	[2]	(72)	[2]	8	[2]
Real Estate Secured - Residential [Member] | Others [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	40	[3]	0	[3]	99	[3]	2	[3]
Pre-Modification Recorded Investment	2,912	[3]	0	[3]	8,323	[3]	1,006	[3]
Post-Modification Recorded Investment	2,912	[3]	0	[3]	8,323	[3]	1,006	[3]
Financial Effect Of Modification On Recorded Investment	0	[1],[3]	0	[1],[3]	0	[1],[3]	0	[1],[3]
Financial Effect Of Modification On Interest	0	[2],[3]	0	[2],[3]	0	[2],[3]	0	[2],[3]
Real Estate Secured - Residential [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	5		0		13		3
Recorded Investment Subsequently Defaulted	509		0		1,290		1,339
Real Estate Secured - Commercial [Member] | Combination Of Modification Types [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	0		0		1		0
Pre-Modification Recorded Investment	0		0		1,436		0
Post-Modification Recorded Investment	0		0		1,436		0
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	0	[2]	0	[2]	(196)	[2]	0	[2]
Real Estate Secured - Commercial [Member] | Others [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	5	[3]	0	[3]	12	[3]	4	[3]
Pre-Modification Recorded Investment	949	[3]	0	[3]	2,499	[3]	10,662	[3]
Post-Modification Recorded Investment	949	[3]	0	[3]	2,499	[3]	10,662	[3]
Financial Effect Of Modification On Recorded Investment	0	[1],[3]	0	[1],[3]	0	[1],[3]	0	[1],[3]
Financial Effect Of Modification On Interest	0	[2],[3]	0	[2],[3]	0	[2],[3]	0	[2],[3]
Real Estate Secured - Commercial [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	0		0		3		0
Recorded Investment Subsequently Defaulted	0		0		447		0
Consumer [Member] | Combination Of Modification Types [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	0		0		0		0
Pre-Modification Recorded Investment	0		0		0		0
Post-Modification Recorded Investment	0		0		0		0
Financial Effect Of Modification On Recorded Investment	0	[1]	0	[1]	0	[1]	0	[1]
Financial Effect Of Modification On Interest	0	[2]	0	[2]	0	[2]	0	[2]
Consumer [Member] | Others [Member]
Financing Receivable Modifications [Line Items]
Number Of Loans	63	[3]	0	[3]	150	[3]	0	[3]
Pre-Modification Recorded Investment	741	[3]	0	[3]	1,397	[3]	0	[3]
Post-Modification Recorded Investment	741	[3]	0	[3]	1,397	[3]	0	[3]
Financial Effect Of Modification On Recorded Investment	0	[1],[3]	0	[1],[3]	0	[1],[3]	0	[1],[3]
Financial Effect Of Modification On Interest	0	[2],[3]	0	[2],[3]	0	[2],[3]	0	[2],[3]
Consumer [Member] | Subsequently Defaulted [Member]
Financing Receivable Modifications [Line Items]
Number Of Contracts Subsequently Defaulted	14		0		33		0
Recorded Investment Subsequently Defaulted	$ 66		$ 0		$ 205		$ 0

[1] Financial effects impacting the recorded investment include principal payments, advances, charge-offs, and capitalized past-due amounts.

[2] Represents the present value of interest rate concessions discounted at the effective rate of the original loan.

[3] Bankruptcies and maturity date extensions.