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Amount of financing receivable on nonaccrual status with no allowance for credit loss.

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Amount of financing receivable on nonaccrual status.

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Amount of financing receivable past due.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Loans and Allowance for Credit Losses - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Proceeds from sales of loans held for sale			$ 88,609,000	$ 299,132,000
Nonaccrual Loans	$ 58,219,000		58,219,000		$ 87,823,000
Restructured loans	7,700,000		7,700,000		10,800,000
Total Past Due	78,909,000		78,909,000		99,644,000
Non accrual loans with no related allowance for credit losses	50,460,000		50,460,000		42,122,000
Accrued interest on loans	50,400,000		$ 50,400,000		58,800,000
Number of reasonable and supportable forecast period			1 year
Commitments to lend to borrowers with loan modifications classified as TDR's	$ 0	$ 0	$ 0	$ 0
Number of Contracts	0		0
Default payment of troubled restructuring	$ 0		$ 0
Real Estate Residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Contracts		1		1
Default payment of troubled restructuring		$ 441,000		$ 441,000
Minimum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of reasonable and supportable forecast period			1 year
Maximum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of reasonable and supportable forecast period			3 years
Individually Evaluated Loans and Collateral Dependent Assets [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans associated allowance			$ 2,800,000		600,000
Greater than 90 days Past Due and Accruing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	$ 1,265,000		1,265,000		$ 1,952,000
Consumer Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Proceeds from sales of loans held for sale			$ 88,600,000	$ 299,100,000