Loans and Lease Finance Receivables and Allowance for Credit Losses - Additional Information (Detail)		3 Months Ended		6 Months Ended
	Jan. 07, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2022 USD ($) Loan	Jun. 30, 2021 USD ($) Loan	Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross		$ 8,680,221,000					$ 8,680,221,000		$ 7,879,537,000
Loans pledged as collateral		4,270,000,000					4,270,000,000		3,960,000,000
Net charge-offs								$ 2,900,000
Recovery net							498,000
Loans held-for-sale			$ 0					0	0
Impaired, at carrying value		5,200,000					5,200,000
Allowance for Credit Losses	$ 4,900,000	80,200,000					80,200,000		65,000,000.0
Reserve for credit risk for undisbursed commitments		8,000,000.0					8,000,000.0		8,000,000.0
Allocation of allowance to troubled debt restructuring		0					0		0
Increase in reserve for unfunded loan commitments		$ 0	$ 1,000,000				0	$ 1,000,000
Percentage of Increase Decrease In Macro Economic Factors					5.40%
Allowance For Credit Losses Increase Decrease							15,200,000
Provision For Credit Losses							$ 6,100,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | Loan							0	0
Forecast [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Increase Decrease In Macro Economic Factors				5.00%		4.60%
GDP [Member] | Forecast [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Increase Decrease In Macro Economic Factors				2.50%	0.80%	0.50%
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total gross loan portfolio (excluding PCI loans)		80.12%					80.12%
Notes receivable gross		$ 6,643,628,000					$ 6,643,628,000		5,789,730,000
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total gross loan portfolio (excluding PCI loans)		76.43%					76.43%
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross		$ 940,583,000					$ 940,583,000		811,691,000
Performing Financing Receivable [Member] | Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans classified as troubled debt restructured		2,300,000					2,300,000
Performing Financing Receivable [Member] | Single-family Residential Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans classified as troubled debt restructured		1,000,000.0					1,000,000.0
Performing Financing Receivable [Member] | Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans classified as troubled debt restructured		1,900,000					1,900,000
Loans, Excluding PCI Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross		273,600,000					273,600,000		386,200,000
Allowance for Credit Losses		67,000,000.0					67,000,000.0
Loans, Excluding PCI Loans [Member] | Agribusiness Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross		$ 52,400,000					$ 52,400,000		$ 34,500,000
Loans, Excluding PCI Loans [Member] | Loans Secured by Farmland [Member] | Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total gross loan portfolio (excluding PCI loans)		7.52%					7.52%		6.29%
Notes receivable gross		$ 499,600,000					$ 499,600,000		$ 364,400,000
Loans, Excluding PCI Loans [Member] | Loans Secured by Farmland [Member] | Loans Secured by Dairy & Livestock Land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross		132,100,000					132,100,000
Loans, Excluding PCI Loans [Member] | Loans Secured by Farmland [Member] | Loans Secured by Dairy & Livestock Land [Member] | Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross									134,900,000
Loans, Excluding PCI Loans [Member] | Loans Secured by Farmland [Member] | Loans Secured by Agricultural Land [Member] | Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable gross		$ 367,500,000					367,500,000		$ 229,500,000
Suncrest Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recovery net							500,000
PCD Loans	$ 8,600,000						8,600,000
Provision For Credit Losses							$ 4,900,000
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total gross loan portfolio (excluding PCI loans)		0.93%					0.93%		0.84%
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total gross loan portfolio (excluding PCI loans)		0.92%					0.92%		0.82%