Loans and Leases - Credit Quality (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	$ 833,275,000	$ 1,524,195,000
2022	1,361,247,000	1,052,017,000
2021	918,895,000	865,577,000
2020	700,846,000	450,178,000
2019	397,235,000	170,031,000
Prior	369,518,000	286,403,000
Revolving Loans Amortized Cost Basis	622,316,000	628,422,000
Revolving Loans Converted to Term	653,000
Total	5,203,985,000	4,976,948,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023	6,000
2022	257,000
2021	314,000
2020	67,000
2019	390,000
Prior	211,000
Revolving Loans Amortized Cost Basis	3,939,000
Revolving Loans Converted to Term	0
Total	5,184,000
Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	828,313,000	1,520,594,000
2022	1,333,248,000	1,009,619,000
2021	901,857,000	842,328,000
2020	694,405,000	435,435,000
2019	386,719,000	167,660,000
Prior	351,617,000	281,371,000
Revolving Loans Amortized Cost Basis	573,758,000	601,419,000
Revolving Loans Converted to Term	653,000
Total	5,070,570,000	4,858,551,000
Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	1,238,000	3,601,000
2022	21,336,000	42,174,000
2021	3,132,000	21,452,000
2020	5,821,000	14,743,000
2019	10,074,000	111,000
Prior	15,681,000	3,943,000
Revolving Loans Amortized Cost Basis	26,159,000	21,667,000
Revolving Loans Converted to Term	0
Total	83,441,000	107,691,000
Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	3,724,000	0
2022	6,663,000	224,000
2021	13,906,000	1,797,000
2020	620,000	0
2019	442,000	2,260,000
Prior	2,220,000	1,089,000
Revolving Loans Amortized Cost Basis	22,399,000	5,336,000
Revolving Loans Converted to Term	0
Total	49,974,000	10,706,000
Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	252,939,000	357,249,000
2022	401,914,000	274,817,000
2021	248,717,000	175,335,000
2020	146,547,000	39,430,000
2019	28,692,000	24,185,000
Prior	82,827,000	78,799,000
Revolving Loans Amortized Cost Basis	195,957,000	193,095,000
Total	1,357,593,000	1,142,910,000
Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	11,000	41,000
2022	257,000	104,000
2021	131,000	483,000
2020	2,768,000	340,000
2019	36,000	553,000
Prior	1,317,000	1,222,000
Revolving Loans Amortized Cost Basis	1,116,000	629,000
Total	5,636,000	3,372,000
Commercial, Financial and Agricultural [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	130,755,000	235,796,000
2022	137,051,000	176,266,000
2021	143,756,000	50,714,000
2020	26,745,000	36,373,000
2019	25,274,000	28,235,000
Prior	40,973,000	48,631,000
Revolving Loans Amortized Cost Basis	484,516,000	512,788,000
Revolving Loans Converted to Term	653,000
Total	989,723,000	1,088,928,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023	6,000
2022	50,000
2021	314,000
2020	67,000
2019	390,000
Prior	161,000
Revolving Loans Amortized Cost Basis	3,889,000
Revolving Loans Converted to Term	0
Total	4,877,000
Commercial, Financial and Agricultural [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	130,755,000	233,064,000
2022	121,402,000	148,033,000
2021	135,550,000	41,091,000
2020	26,745,000	28,269,000
2019	19,029,000	28,209,000
Prior	40,973,000	48,631,000
Revolving Loans Amortized Cost Basis	455,076,000	487,818,000
Revolving Loans Converted to Term	653,000
Total	930,183,000	1,015,240,000
Commercial, Financial and Agricultural [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	2,732,000
2022	13,454,000	28,220,000
2021	0	9,623,000
2020	0	8,104,000
2019	6,029,000	26,000
Prior	0	0
Revolving Loans Amortized Cost Basis	15,251,000	19,829,000
Revolving Loans Converted to Term	0
Total	34,734,000	68,534,000
Commercial, Financial and Agricultural [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	2,195,000	13,000
2021	8,206,000	0
2020	0	0
2019	216,000	0
Prior	0	0
Revolving Loans Amortized Cost Basis	14,189,000	5,141,000
Revolving Loans Converted to Term	0
Total	24,806,000	5,154,000
Real Estate-Commercial [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	483,089,000	878,572,000
2022	844,488,000	688,605,000
2021	648,033,000	738,293,000
2020	610,521,000	333,646,000
2019	329,669,000	120,341,000
Prior	309,129,000	212,471,000
Revolving Loans Amortized Cost Basis	77,869,000	56,027,000
Revolving Loans Converted to Term	0
Total	3,302,798,000	3,027,955,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Prior	50,000
Revolving Loans Converted to Term	0
Total	50,000
Real Estate-Commercial [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	480,527,000	877,703,000
2022	841,529,000	680,432,000
2021	642,133,000	724,941,000
2020	604,700,000	332,702,000
2019	329,443,000	118,034,000
Prior	296,802,000	208,974,000
Revolving Loans Amortized Cost Basis	74,947,000	54,139,000
Revolving Loans Converted to Term	0
Total	3,270,081,000	2,996,925,000
Real Estate-Commercial [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	1,238,000	869,000
2022	227,000	8,173,000
2021	3,132,000	11,582,000
2020	5,821,000	944,000
2019	0	85,000
Prior	10,416,000	3,002,000
Revolving Loans Amortized Cost Basis	0	1,838,000
Revolving Loans Converted to Term	0
Total	20,834,000	26,493,000
Real Estate-Commercial [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	1,324,000	0
2022	2,732,000	0
2021	2,768,000	1,770,000
2020	0	0
2019	226,000	2,222,000
Prior	1,911,000	495,000
Revolving Loans Amortized Cost Basis	2,922,000	50,000
Revolving Loans Converted to Term	0
Total	11,883,000	4,537,000
Real Estate-Construction [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	114,527,000	243,983,000
2022	227,866,000	58,266,000
2021	7,071,000	8,341,000
2020	2,600,000	40,365,000
2019	4,286,000	191,000
Prior	7,476,000	442,000
Revolving Loans Amortized Cost Basis	30,636,000	30,223,000
Revolving Loans Converted to Term	0
Total	394,462,000	381,811,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2022	207,000
Revolving Loans Converted to Term	0
Total	207,000
Real Estate-Construction [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	112,127,000	243,983,000
2022	218,637,000	52,485,000
2021	4,139,000	8,341,000
2020	2,600,000	34,670,000
2019	241,000	191,000
Prior	2,211,000	442,000
Revolving Loans Amortized Cost Basis	14,440,000	30,223,000
Revolving Loans Converted to Term	0
Total	354,395,000	370,335,000
Real Estate-Construction [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	7,655,000	5,781,000
2021	0	0
2020	0	5,695,000
2019	4,045,000	0
Prior	5,265,000	0
Revolving Loans Amortized Cost Basis	10,908,000	0
Revolving Loans Converted to Term	0
Total	27,873,000	11,476,000
Real Estate-Construction [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	2,400,000	0
2022	1,574,000	0
2021	2,932,000	0
2020	0	0
2019	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	5,288,000	0
Revolving Loans Converted to Term	0
Total	12,194,000	0
Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	104,904,000	165,844,000
2022	151,842,000	128,880,000
2021	120,035,000	68,229,000
2020	60,980,000	39,794,000
2019	38,006,000	21,264,000
Prior	11,940,000	24,859,000
Revolving Loans Amortized Cost Basis	29,295,000	29,384,000
Revolving Loans Converted to Term	0
Total	517,002,000	478,254,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Revolving Loans Amortized Cost Basis	50,000
Revolving Loans Converted to Term	0
Total	50,000
Real Estate-Residential Secured for Business Purpose [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	104,904,000	165,844,000
2022	151,680,000	128,669,000
2021	120,035,000	67,955,000
2020	60,360,000	39,794,000
2019	38,006,000	21,226,000
Prior	11,631,000	23,324,000
Revolving Loans Amortized Cost Basis	29,295,000	29,239,000
Revolving Loans Converted to Term	0
Total	515,911,000	476,051,000
Real Estate-Residential Secured for Business Purpose [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	0	0
2021	0	247,000
2020	0	0
2019	0	0
Prior	0	941,000
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0
Total	0	1,188,000
Real Estate-Residential Secured for Business Purpose [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	162,000	211,000
2021	0	27,000
2020	620,000	0
2019	0	38,000
Prior	309,000	594,000
Revolving Loans Amortized Cost Basis	0	145,000
Revolving Loans Converted to Term	0
Total	1,091,000	1,015,000
Real Estate-Residential Secured for Personal Purpose [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	139,765,000	258,293,000
2022	328,536,000	211,686,000
2021	206,328,000	141,288,000
2020	130,906,000	24,146,000
2019	22,798,000	18,579,000
Prior	80,564,000	76,295,000
Revolving Loans Amortized Cost Basis	118,000	108,000
Total	909,015,000	730,395,000
Real Estate-Residential Secured for Personal Purpose [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	139,765,000	258,293,000
2022	328,383,000	211,638,000
2021	206,285,000	140,822,000
2020	128,157,000	23,827,000
2019	22,798,000	18,273,000
Prior	79,296,000	75,126,000
Revolving Loans Amortized Cost Basis	118,000	108,000
Total	904,802,000	728,087,000
Real Estate-Residential Secured for Personal Purpose [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	153,000	48,000
2021	43,000	466,000
2020	2,749,000	319,000
2019	0	306,000
Prior	1,268,000	1,169,000
Revolving Loans Amortized Cost Basis	0	0
Total	4,213,000	2,308,000
Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	511,000	2,945,000
2022	2,567,000	642,000
2021	510,000	491,000
2020	409,000	192,000
2019	165,000	362,000
Prior	1,463,000	1,568,000
Revolving Loans Amortized Cost Basis	173,657,000	170,499,000
Total	179,282,000	176,699,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2019	85,000
Total	85,000
Real Estate-Home Equity Secured for Personal Purpose [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	511,000	2,945,000
2022	2,567,000	642,000
2021	510,000	491,000
2020	409,000	192,000
2019	165,000	205,000
Prior	1,463,000	1,565,000
Revolving Loans Amortized Cost Basis	172,541,000	169,870,000
Total	178,166,000	175,910,000
Real Estate-Home Equity Secured for Personal Purpose [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	157,000
Prior	0	3,000
Revolving Loans Amortized Cost Basis	1,116,000	629,000
Total	1,116,000	789,000
Loans to Individuals [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	1,831,000	1,581,000
2022	894,000	857,000
2021	530,000	554,000
2020	107,000	247,000
2019	48,000	138,000
Prior	1,041,000	1,379,000
Revolving Loans Amortized Cost Basis	23,298,000	23,117,000
Total	27,749,000	27,873,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023	215,000
2022	82,000
2020	5,000
2019	29,000
Prior	21,000
Revolving Loans Amortized Cost Basis	155,000
Total	507,000
Loans to Individuals [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	1,831,000	1,581,000
2022	894,000	857,000
2021	530,000	554,000
2020	107,000	247,000
2019	48,000	138,000
Prior	1,004,000	1,340,000
Revolving Loans Amortized Cost Basis	23,298,000	23,117,000
Total	27,712,000	27,834,000
Loans to Individuals [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior	37,000	39,000
Revolving Loans Amortized Cost Basis	0	0
Total	37,000	39,000
Lease Financings [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	110,843,000	94,471,000
2022	70,174,000	61,736,000
2021	41,480,000	33,485,000
2020	17,893,000	15,185,000
2019	5,717,000	5,659,000
Prior	1,076,000	779,000
Revolving Loans Amortized Cost Basis	0	0
Total	247,183,000	211,315,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2022	174,000
2021	144,000
2020	71,000
2019	20,000
Prior	1,000
Total	410,000
Lease Financings [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	110,832,000	94,430,000
2022	70,070,000	61,680,000
2021	41,392,000	33,468,000
2020	17,874,000	15,164,000
2019	5,681,000	5,569,000
Prior	1,064,000	768,000
Revolving Loans Amortized Cost Basis	0	0
Total	246,913,000	211,079,000
Lease Financings [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	11,000	41,000
2022	104,000	56,000
2021	88,000	17,000
2020	19,000	21,000
2019	36,000	90,000
Prior	12,000	11,000
Revolving Loans Amortized Cost Basis	0	0
Total	270,000	236,000
Financing Receivable
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2023	252,950,000	357,290,000
2022	402,171,000	274,921,000
2021	248,848,000	175,818,000
2020	149,315,000	39,770,000
2019	28,728,000	24,738,000
Prior	84,144,000	80,021,000
Revolving Loans Amortized Cost Basis	197,073,000	193,724,000
Total	1,363,229,000	$ 1,146,282,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023	215,000
2022	256,000
2021	144,000
2020	76,000
2019	134,000
Prior	22,000
Revolving Loans Amortized Cost Basis	155,000
Total	$ 1,002,000