A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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Allowance for Loan Losses - Allowance for Loan Losses and Recorded Investment in Loans by Portfolio Segment (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Total ending allowance balance	$ 17,798	$ 17,071	$ 16,394	$ 15,586	$ 15,027	$ 14,837
Total ending loans balance	8,358			$ 3,451
Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total ending allowance balance	121
Allowance for Loan Losses [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Individually evaluated for impairment	924		184
Allowance For Loan Losses, Collectively evaluated for impairment	16,874		16,210
Total ending allowance balance	17,798		16,394
Allowance for Loan Losses [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Loans acquired with deteriorated credit quality	0		0
Commercial [Member] \| Allowance for Loan Losses [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Individually evaluated for impairment	924		184
Allowance For Loan Losses, Collectively evaluated for impairment	9,657		8,909
Total ending allowance balance	10,581		9,093
Commercial [Member] \| Allowance for Loan Losses [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Loans acquired with deteriorated credit quality	0		0
Real Estate [Member] \| Allowance for Loan Losses [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Collectively evaluated for impairment	1,574		2,188
Total ending allowance balance	1,574		2,188
Real Estate [Member] \| Allowance for Loan Losses [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Loans acquired with deteriorated credit quality	0		0
Consumer [Member] \| Allowance for Loan Losses [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Collectively evaluated for impairment	4,613		4,083
Total ending allowance balance	4,613		4,083
Consumer [Member] \| Allowance for Loan Losses [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Loans acquired with deteriorated credit quality	0		0
Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans: Individually evaluated for impairment	8,358		7,187
Loans: Collectively evaluated for impairment	2,959,121		2,834,034
Total ending loans balance	2,967,479		2,841,221
Loans [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0		0
Loans [Member] \| Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans: Individually evaluated for impairment	8,358		7,187
Loans: Collectively evaluated for impairment	1,696,067		1,667,942
Total ending loans balance	1,704,425		1,675,129
Loans [Member] \| Commercial [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0		0
Loans [Member] \| Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans: Collectively evaluated for impairment	653,286		608,575
Total ending loans balance	653,286		608,575
Loans [Member] \| Real Estate [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0		0
Loans [Member] \| Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans: Collectively evaluated for impairment	537,866		462,529
Total ending loans balance	537,866		462,529
Loans [Member] \| Consumer [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0		0
Mortgage Warehousing [Member] \| Allowance for Loan Losses [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Collectively evaluated for impairment	1,030		1,030
Total ending allowance balance	1,030		1,030
Mortgage Warehousing [Member] \| Allowance for Loan Losses [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance For Loan Losses, Loans acquired with deteriorated credit quality	0		0
Mortgage Warehousing [Member] \| Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans: Collectively evaluated for impairment	71,902		94,988
Total ending loans balance	71,902		94,988
Mortgage Warehousing [Member] \| Loans [Member] \| Loans Purchased With Evidence of Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	$ 0		$ 0