Loans and Leases (Impaired Loans) (Detail) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Financing Receivable Impaired [Line Items]
Loans written down to fair value of collateral	$ 34,511,000		$ 43,363,000
Total impaired loans without a related reserve	156,140,000		195,033,000
Direct charge-offs	26,752,000		25,986,000
Subsequently Impaired Loans	5,896,000		9,498,000
Purchased Impaired Loans	112,997,000		138,445,000
Impaired Loans Without A Related Reserve [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	182,892,000		221,019,000
Recorded Investment in Impaired Loans	156,140,000	[1]	195,033,000	[2]
Related Charge-offs	26,752,000		25,986,000
Average Recorded Investment in Impaired Loans	155,434,000	[3]	196,848,000	[3]
Interest Income Recognized	2,048,000		2,903,000
Impaired Loans Without A Related Reserve [Member] | Originated Loans And Leases [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	73,346,000		88,900,000
Recorded Investment in Impaired Loans	49,039,000		66,086,000
Related Charge-offs	24,307,000		22,814,000
Average Recorded Investment in Impaired Loans	47,805,000	[3]	65,341,000	[3]
Interest Income Recognized	583,000		749,000
Impaired Loans Without A Related Reserve [Member] | Purchased Loans And Leases [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	109,546,000		132,119,000
Recorded Investment in Impaired Loans	107,101,000		128,947,000
Related Charge-offs	2,445,000		3,172,000
Average Recorded Investment in Impaired Loans	107,629,000	[3]	131,507,000	[3]
Interest Income Recognized	1,465,000		2,154,000
Impaired Loans Without A Related Reserve [Member] | Commercial, Financial, And Agricultural [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	21,203,000		31,196,000
Recorded Investment in Impaired Loans	18,289,000		28,034,000
Related Charge-offs	2,914,000		3,162,000
Average Recorded Investment in Impaired Loans	18,410,000	[3]	29,316,000	[3]
Interest Income Recognized	238,000		390,000
Impaired Loans Without A Related Reserve [Member] | Real Estate - Construction [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	11,286,000		17,851,000
Recorded Investment in Impaired Loans	10,687,000		14,215,000
Related Charge-offs	599,000		3,636,000
Average Recorded Investment in Impaired Loans	10,826,000	[3]	14,715,000	[3]
Interest Income Recognized	97,000		140,000
Impaired Loans Without A Related Reserve [Member] | Real Estate Secured - Residential [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	23,047,000		28,308,000
Recorded Investment in Impaired Loans	22,414,000		27,645,000
Related Charge-offs	633,000		663,000
Average Recorded Investment in Impaired Loans	22,953,000	[3]	27,800,000	[3]
Interest Income Recognized	278,000		297,000
Impaired Loans Without A Related Reserve [Member] | Real Estate Secured - Commercial [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	127,356,000		143,664,000
Recorded Investment in Impaired Loans	104,750,000		125,139,000
Related Charge-offs	22,606,000		18,525,000
Average Recorded Investment in Impaired Loans	103,245,000	[3]	125,003,000	[3]
Interest Income Recognized	1,435,000		2,076,000
Impaired Loans Without A Related Reserve [Member] | Consumer [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	0		0
Recorded Investment in Impaired Loans	0		0
Related Charge-offs	0		0
Average Recorded Investment in Impaired Loans	0	[3]	14,000	[3]
Interest Income Recognized	0		0
Impaired Loans With A Related Reserve [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	57,192,000		88,795,000
Recorded Investment in Impaired Loans	48,932,000		67,841,000
Related Charge-offs	8,260,000		20,954,000
Related Specific Allowance	12,957,000		13,625,000
Average Recorded Investment in Impaired Loans	50,761,000	[3]	65,585,000	[3]
Interest Income Recognized	668,000		1,317,000
Impaired Loans With A Related Reserve [Member] | Originated Loans And Leases [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	51,046,000		78,015,000
Recorded Investment in Impaired Loans	43,036,000		58,343,000
Related Charge-offs	8,010,000		19,672,000
Related Specific Allowance	11,556,000		11,612,000
Average Recorded Investment in Impaired Loans	44,763,000	[3]	55,881,000	[3]
Interest Income Recognized	561,000		1,172,000
Impaired Loans With A Related Reserve [Member] | Purchased Loans And Leases [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	6,146,000		10,780,000
Recorded Investment in Impaired Loans	5,896,000		9,498,000
Related Charge-offs	250,000		1,282,000
Related Specific Allowance	1,401,000		2,013,000
Average Recorded Investment in Impaired Loans	5,998,000	[3]	9,704,000	[3]
Interest Income Recognized	107,000		145,000
Impaired Loans With A Related Reserve [Member] | Commercial, Financial, And Agricultural [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	7,941,000		6,864,000
Recorded Investment in Impaired Loans	7,941,000		5,879,000
Related Charge-offs	0		985,000
Related Specific Allowance	4,307,000		3,008,000
Average Recorded Investment in Impaired Loans	8,385,000	[3]	5,893,000	[3]
Interest Income Recognized	56,000		154,000
Impaired Loans With A Related Reserve [Member] | Real Estate - Construction [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	7,823,000		15,202,000
Recorded Investment in Impaired Loans	3,090,000		7,288,000
Related Charge-offs	4,733,000		7,914,000
Related Specific Allowance	705,000		1,819,000
Average Recorded Investment in Impaired Loans	3,139,000	[3]	5,831,000	[3]
Interest Income Recognized	27,000		228,000
Impaired Loans With A Related Reserve [Member] | Real Estate Secured - Residential [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	23,836,000		37,499,000
Recorded Investment in Impaired Loans	22,218,000		35,153,000
Related Charge-offs	1,618,000		2,346,000
Related Specific Allowance	2,634,000		4,753,000
Average Recorded Investment in Impaired Loans	24,350,000	[3]	35,273,000	[3]
Interest Income Recognized	259,000		554,000
Impaired Loans With A Related Reserve [Member] | Real Estate Secured - Commercial [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	16,543,000		27,238,000
Recorded Investment in Impaired Loans	14,634,000		17,529,000
Related Charge-offs	1,909,000		9,709,000
Related Specific Allowance	5,197,000		3,827,000
Average Recorded Investment in Impaired Loans	13,792,000	[3]	16,546,000	[3]
Interest Income Recognized	305,000		325,000
Impaired Loans With A Related Reserve [Member] | Consumer [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	1,049,000		1,992,000
Recorded Investment in Impaired Loans	1,049,000		1,992,000
Related Charge-offs	0		0
Related Specific Allowance	114,000		218,000
Average Recorded Investment in Impaired Loans	1,095,000	[3]	2,042,000	[3]
Interest Income Recognized	21,000		56,000
Impaired Loans [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	240,084,000		309,814,000
Recorded Investment in Impaired Loans	205,072,000		262,874,000
Related Charge-offs	35,012,000		46,940,000
Related Specific Allowance	12,957,000		13,625,000
Average Recorded Investment in Impaired Loans	206,195,000	[3]	262,433,000	[3]
Interest Income Recognized	2,716,000		4,220,000
Impaired Loans [Member] | Originated Loans And Leases [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	124,392,000		166,915,000
Recorded Investment in Impaired Loans	92,075,000		124,429,000
Related Charge-offs	32,317,000		42,486,000
Related Specific Allowance	11,556,000		11,612,000
Average Recorded Investment in Impaired Loans	92,568,000	[3]	121,222,000	[3]
Interest Income Recognized	1,144,000		1,921,000
Impaired Loans [Member] | Purchased Loans And Leases [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	115,692,000	[4]	142,899,000	[5]
Recorded Investment in Impaired Loans	112,997,000	[4]	138,445,000	[5]
Related Charge-offs	2,695,000	[4]	4,454,000	[5]
Related Specific Allowance	1,401,000	[4]	2,013,000	[5]
Average Recorded Investment in Impaired Loans	113,627,000	[3],[4]	141,211,000	[3],[5]
Interest Income Recognized	1,572,000	[4]	2,299,000	[5]
Impaired Loans [Member] | Commercial, Financial, And Agricultural [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	29,144,000		38,060,000
Recorded Investment in Impaired Loans	26,230,000		33,913,000
Related Charge-offs	2,914,000		4,147,000
Related Specific Allowance	4,307,000		3,008,000
Average Recorded Investment in Impaired Loans	26,795,000	[3]	35,209,000	[3]
Interest Income Recognized	294,000		544,000
Impaired Loans [Member] | Real Estate - Construction [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	19,109,000		33,053,000
Recorded Investment in Impaired Loans	13,777,000		21,503,000
Related Charge-offs	5,332,000		11,550,000
Related Specific Allowance	705,000		1,819,000
Average Recorded Investment in Impaired Loans	13,965,000	[3]	20,546,000	[3]
Interest Income Recognized	124,000		368,000
Impaired Loans [Member] | Real Estate Secured - Residential [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	46,883,000		65,807,000
Recorded Investment in Impaired Loans	44,632,000		62,798,000
Related Charge-offs	2,251,000		3,009,000
Related Specific Allowance	2,634,000		4,753,000
Average Recorded Investment in Impaired Loans	47,303,000	[3]	63,073,000	[3]
Interest Income Recognized	537,000		851,000
Impaired Loans [Member] | Real Estate Secured - Commercial [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	143,899,000		170,902,000
Recorded Investment in Impaired Loans	119,384,000		142,668,000
Related Charge-offs	24,515,000		28,234,000
Related Specific Allowance	5,197,000		3,827,000
Average Recorded Investment in Impaired Loans	117,037,000	[3]	141,549,000	[3]
Interest Income Recognized	1,740,000		2,401,000
Impaired Loans [Member] | Consumer [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	1,049,000		1,992,000
Recorded Investment in Impaired Loans	1,049,000		1,992,000
Related Charge-offs	0		0
Related Specific Allowance	114,000		218,000
Average Recorded Investment in Impaired Loans	1,095,000	[3]	2,056,000	[3]
Interest Income Recognized	$ 21,000		$ 56,000

[1] $34,511 of the $156,140 total impaired loans without a related reserve represents loans that had been written down to the fair value of the underlying collateral adjusted for selling costs through direct charge-offs of $26,752.

[2] $43,363 of the $195,033 total impaired loans without a related reserve represents loans that had been written down to the fair value of the underlying collateral adjusted for selling costs through direct charge-offs of $25,986.

[3] Average recorded investment in impaired loans is calculated on a quarterly basis using daily balances.

[4] $5,896 of the $112,997 purchased impaired loans were subsequently impaired after being acquired.

[5] $9,498 of the $138,445 purchased impaired loans were subsequently impaired after being acquired.