Loans and Leases - Credit Quality (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	$ 949,352,000	$ 833,275,000
2023	689,996,000	1,361,247,000
2022	1,179,625,000	918,895,000
2021	793,509,000	700,846,000
2020	612,928,000	397,235,000
Prior	559,868,000	369,518,000
Revolving Loans Amortized Cost Basis	592,715,000	622,316,000
Revolving Loans Converted to Term	871,000
Total	5,378,864,000	5,203,985,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2024	69,000
2021	72,000
2020	9,000
Prior	66,000
Revolving Loans Amortized Cost Basis	3,245,000
Revolving Loans Converted to Term	0
Total	3,461,000
Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	943,172,000	828,313,000
2023	682,768,000	1,333,248,000
2022	1,145,754,000	901,857,000
2021	785,210,000	694,405,000
2020	605,137,000	386,719,000
Prior	539,899,000	351,617,000
Revolving Loans Amortized Cost Basis	544,116,000	573,758,000
Revolving Loans Converted to Term	871,000
Total	5,246,927,000	5,070,570,000
Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	5,932,000	1,238,000
2023	6,728,000	21,336,000
2022	25,139,000	3,132,000
2021	849,000	5,821,000
2020	3,438,000	10,074,000
Prior	12,213,000	15,681,000
Revolving Loans Amortized Cost Basis	27,106,000	26,159,000
Revolving Loans Converted to Term	0
Total	81,405,000	83,441,000
Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	248,000	3,724,000
2023	500,000	6,663,000
2022	8,732,000	13,906,000
2021	7,450,000	620,000
2020	4,353,000	442,000
Prior	7,756,000	2,220,000
Revolving Loans Amortized Cost Basis	21,493,000	22,399,000
Revolving Loans Converted to Term	0
Total	50,532,000	49,974,000
Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	111,630,000	252,939,000
2023	287,085,000	401,914,000
2022	406,211,000	248,717,000
2021	219,517,000	146,547,000
2020	128,077,000	28,692,000
Prior	91,654,000	82,827,000
Revolving Loans Amortized Cost Basis	197,617,000	195,957,000
Total	1,441,791,000	1,357,593,000
Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	197,000	11,000
2023	168,000	257,000
2022	636,000	131,000
2021	69,000	2,768,000
2020	2,861,000	36,000
Prior	827,000	1,317,000
Revolving Loans Amortized Cost Basis	1,170,000	1,116,000
Total	5,928,000	5,636,000
Commercial, Financial and Agricultural [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	236,547,000	130,755,000
2023	80,442,000	137,051,000
2022	94,603,000	143,756,000
2021	101,924,000	26,745,000
2020	16,408,000	25,274,000
Prior	50,730,000	40,973,000
Revolving Loans Amortized Cost Basis	456,310,000	484,516,000
Revolving Loans Converted to Term	871,000
Total	1,037,835,000	989,723,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2024	69,000
2021	72,000
2020	9,000
Prior	31,000
Revolving Loans Amortized Cost Basis	2,745,000
Revolving Loans Converted to Term	0
Total	2,926,000
Commercial, Financial and Agricultural [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	232,925,000	130,755,000
2023	73,453,000	121,402,000
2022	68,205,000	135,550,000
2021	95,135,000	26,745,000
2020	16,403,000	19,029,000
Prior	44,329,000	40,973,000
Revolving Loans Amortized Cost Basis	411,413,000	455,076,000
Revolving Loans Converted to Term	871,000
Total	942,734,000	930,183,000
Commercial, Financial and Agricultural [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	3,622,000	0
2023	6,489,000	13,454,000
2022	24,423,000	0
2021	166,000	0
2020	5,000	6,029,000
Prior	0	0
Revolving Loans Amortized Cost Basis	27,106,000	15,251,000
Revolving Loans Converted to Term	0
Total	61,811,000	34,734,000
Commercial, Financial and Agricultural [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	0
2023	500,000	2,195,000
2022	1,975,000	8,206,000
2021	6,623,000	0
2020	0	216,000
Prior	6,401,000	0
Revolving Loans Amortized Cost Basis	17,791,000	14,189,000
Revolving Loans Converted to Term	0
Total	33,290,000	24,806,000
Real Estate-Commercial [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	508,407,000	483,089,000
2023	441,802,000	844,488,000
2022	885,449,000	648,033,000
2021	582,520,000	610,521,000
2020	542,969,000	329,669,000
Prior	485,264,000	309,129,000
Revolving Loans Amortized Cost Basis	84,040,000	77,869,000
Revolving Loans Converted to Term	0
Total	3,530,451,000	3,302,798,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Prior	35,000
Revolving Loans Converted to Term	0
Total	35,000
Real Estate-Commercial [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	506,644,000	480,527,000
2023	441,802,000	841,529,000
2022	882,071,000	642,133,000
2021	581,693,000	604,700,000
2020	538,539,000	329,443,000
Prior	471,734,000	296,802,000
Revolving Loans Amortized Cost Basis	81,145,000	74,947,000
Revolving Loans Converted to Term	0
Total	3,503,628,000	3,270,081,000
Real Estate-Commercial [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	1,763,000	1,238,000
2023	0	227,000
2022	716,000	3,132,000
2021	0	5,821,000
2020	3,028,000	0
Prior	12,213,000	10,416,000
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0
Total	17,720,000	20,834,000
Real Estate-Commercial [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	1,324,000
2023	0	2,732,000
2022	2,662,000	2,768,000
2021	827,000	0
2020	1,402,000	226,000
Prior	1,317,000	1,911,000
Revolving Loans Amortized Cost Basis	2,895,000	2,922,000
Revolving Loans Converted to Term	0
Total	9,103,000	11,883,000
Real Estate-Construction [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	109,875,000	114,527,000
2023	71,770,000	227,866,000
2022	62,167,000	7,071,000
2021	4,226,000	2,600,000
2020	4,103,000	4,286,000
Prior	1,899,000	7,476,000
Revolving Loans Amortized Cost Basis	20,443,000	30,636,000
Revolving Loans Converted to Term	0
Total	274,483,000	394,462,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Revolving Loans Amortized Cost Basis	500,000
Revolving Loans Converted to Term	0
Total	500,000
Real Estate-Construction [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	109,627,000	112,127,000
2023	71,770,000	218,637,000
2022	58,072,000	4,139,000
2021	4,226,000	2,600,000
2020	1,700,000	241,000
Prior	1,899,000	2,211,000
Revolving Loans Amortized Cost Basis	19,636,000	14,440,000
Revolving Loans Converted to Term	0
Total	266,930,000	354,395,000
Real Estate-Construction [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	0
2023	0	7,655,000
2022	0	0
2021	0	0
2020	0	4,045,000
Prior	0	5,265,000
Revolving Loans Amortized Cost Basis	0	10,908,000
Revolving Loans Converted to Term	0
Total	0	27,873,000
Real Estate-Construction [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	248,000	2,400,000
2023	0	1,574,000
2022	4,095,000	2,932,000
2021	0	0
2020	2,403,000	0
Prior	0	0
Revolving Loans Amortized Cost Basis	807,000	5,288,000
Revolving Loans Converted to Term	0
Total	7,553,000	12,194,000
Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	94,523,000	104,904,000
2023	95,982,000	151,842,000
2022	137,406,000	120,035,000
2021	104,839,000	60,980,000
2020	49,448,000	38,006,000
Prior	21,975,000	11,940,000
Revolving Loans Amortized Cost Basis	31,922,000	29,295,000
Revolving Loans Converted to Term	0
Total	536,095,000	517,002,000
Real Estate-Residential Secured for Business Purpose [Member] | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	93,976,000	104,904,000
2023	95,743,000	151,680,000
2022	137,406,000	120,035,000
2021	104,156,000	60,360,000
2020	48,495,000	38,006,000
Prior	21,937,000	11,631,000
Revolving Loans Amortized Cost Basis	31,922,000	29,295,000
Revolving Loans Converted to Term	0
Total	533,635,000	515,911,000
Real Estate-Residential Secured for Business Purpose [Member] | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	547,000	0
2023	239,000	0
2022	0	0
2021	683,000	0
2020	405,000	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0
Total	1,874,000	0
Real Estate-Residential Secured for Business Purpose [Member] | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	0
2023	0	162,000
2022	0	0
2021	0	620,000
2020	548,000	0
Prior	38,000	309,000
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0
Total	586,000	1,091,000
Real Estate-Residential Secured for Personal Purpose [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	25,908,000	139,765,000
2023	203,136,000	328,536,000
2022	356,648,000	206,328,000
2021	195,764,000	130,906,000
2020	124,579,000	22,798,000
Prior	88,937,000	80,564,000
Revolving Loans Amortized Cost Basis	0	118,000
Total	994,972,000	909,015,000
Real Estate-Residential Secured for Personal Purpose [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	25,908,000	139,765,000
2023	203,136,000	328,383,000
2022	356,506,000	206,285,000
2021	195,727,000	128,157,000
2020	121,743,000	22,798,000
Prior	88,147,000	79,296,000
Revolving Loans Amortized Cost Basis	0	118,000
Total	991,167,000	904,802,000
Real Estate-Residential Secured for Personal Purpose [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	0
2023	0	153,000
2022	142,000	43,000
2021	37,000	2,749,000
2020	2,836,000	0
Prior	790,000	1,268,000
Revolving Loans Amortized Cost Basis	0	0
Total	3,805,000	4,213,000
Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	354,000	511,000
2023	352,000	2,567,000
2022	2,281,000	510,000
2021	402,000	409,000
2020	326,000	165,000
Prior	1,201,000	1,463,000
Revolving Loans Amortized Cost Basis	181,920,000	173,657,000
Total	186,836,000	179,282,000
Real Estate-Home Equity Secured for Personal Purpose [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	354,000	511,000
2023	352,000	2,567,000
2022	2,260,000	510,000
2021	402,000	409,000
2020	326,000	165,000
Prior	1,201,000	1,463,000
Revolving Loans Amortized Cost Basis	180,750,000	172,541,000
Total	185,645,000	178,166,000
Real Estate-Home Equity Secured for Personal Purpose [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	0
2023	0	0
2022	21,000	0
2021	0	0
2020	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	1,170,000	1,116,000
Total	1,191,000	1,116,000
Loans to Individuals [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	2,008,000	1,831,000
2023	963,000	894,000
2022	459,000	530,000
2021	300,000	107,000
2020	19,000	48,000
Prior	634,000	1,041,000
Revolving Loans Amortized Cost Basis	16,867,000	23,298,000
Total	21,250,000	27,749,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2024	220,000
2023	135,000
2022	33,000
2021	3,000
Prior	88,000
Revolving Loans Amortized Cost Basis	442,000
Total	921,000
Loans to Individuals [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	2,008,000	1,831,000
2023	963,000	894,000
2022	459,000	530,000
2021	300,000	107,000
2020	19,000	48,000
Prior	610,000	1,004,000
Revolving Loans Amortized Cost Basis	16,867,000	23,298,000
Total	21,226,000	27,712,000
Loans to Individuals [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior	24,000	37,000
Revolving Loans Amortized Cost Basis	0	0
Total	24,000	37,000
Lease Financings [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	83,557,000	110,843,000
2023	82,802,000	70,174,000
2022	47,459,000	41,480,000
2021	23,120,000	17,893,000
2020	6,014,000	5,717,000
Prior	1,709,000	1,076,000
Revolving Loans Amortized Cost Basis	0	0
Total	244,661,000	247,183,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023	238,000
2022	165,000
2021	218,000
2020	14,000
Prior	16,000
Total	651,000
Lease Financings [Member] | Performing
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	83,360,000	110,832,000
2023	82,634,000	70,070,000
2022	46,986,000	41,392,000
2021	23,088,000	17,874,000
2020	5,989,000	5,681,000
Prior	1,696,000	1,064,000
Revolving Loans Amortized Cost Basis	0	0
Total	243,753,000	246,913,000
Lease Financings [Member] | Nonperforming
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	197,000	11,000
2023	168,000	104,000
2022	473,000	88,000
2021	32,000	19,000
2020	25,000	36,000
Prior	13,000	12,000
Revolving Loans Amortized Cost Basis	0	0
Total	908,000	270,000
Financing Receivable
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
2024	111,827,000	252,950,000
2023	287,253,000	402,171,000
2022	406,847,000	248,848,000
2021	219,586,000	149,315,000
2020	130,938,000	28,728,000
Prior	92,481,000	84,144,000
Revolving Loans Amortized Cost Basis	198,787,000	197,073,000
Total	1,447,719,000	$ 1,363,229,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2024	220,000
2023	373,000
2022	198,000
2021	221,000
2020	14,000
Prior	104,000
Revolving Loans Amortized Cost Basis	442,000
Total	$ 1,572,000