Number of financing receivables that have been modified by troubled debt restructurings.

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-Topic 310
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-Section 50
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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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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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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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Loans - Additional Information (Detail)	3 Months Ended		6 Months Ended
Loans - Additional Information (Detail)	Jun. 30, 2018 USD ($) Investment	Jun. 30, 2017 USD ($) Investment	Jun. 30, 2018 USD ($) Investment	Jun. 30, 2017 USD ($) Investment	Dec. 31, 2017 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Outstanding loans to Executive officers, directors, principal shareholders, related interest and parties	$ 55,600,000		$ 55,600,000
Loans held for sale	0		0		$ 35,258,000
Delinquent loans selectively extended to certain borrowers, rate reductions, forbearance of arrears, and extension of maturity dates		$ 19,379,000	$ 4,074,000	$ 24,145,000
Number of loans classified as a non-accrual TDRs \| Investment		16	13	34
Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Delinquent loans selectively extended to certain borrowers, rate reductions, forbearance of arrears, and extension of maturity dates	$ 1,420,000	$ 18,722,000	$ 3,174,000	$ 23,151,000
Number of loans classified as a non-accrual TDRs \| Investment	6	13	12	30
Commercial and Industrial \| Payment Default
Financing Receivable, Recorded Investment [Line Items]
Number of loans classified as a non-accrual TDRs			6
Loan classified as non accrual TDRs	$ 1,700,000		$ 1,700,000
Principal shareholders
Financing Receivable, Recorded Investment [Line Items]
Outstanding loans to Executive officers, directors, principal shareholders, related interest and parties	$ 0		0
Financing Receivable Troubled Debt Restructurings Rate Reductions
Financing Receivable, Recorded Investment [Line Items]
Delinquent loans selectively extended to certain borrowers, rate reductions, forbearance of arrears, and extension of maturity dates			39,900,000
Financing Receivable Troubled Debt Restructurings Forbearance of Arrears
Financing Receivable, Recorded Investment [Line Items]
Delinquent loans selectively extended to certain borrowers, rate reductions, forbearance of arrears, and extension of maturity dates			$ 1,800,000