Loans and Leases - Activity for SBA Loans Held for Sale (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward]
Balance at beginning of period	$ 9,390	$ 6,394
Originations	13,223	18,805
Sales	(15,459)	(19,187)
Principal payoffs and amortization	(14)	(4)
Balance at end of period	7,140	6,008
Real estate loans
Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward]
Balance at beginning of period	5,194	3,746
Originations	9,064	10,433
Sales	(7,756)	(12,028)
Principal payoffs and amortization	(2)	0
Balance at end of period	6,500	2,151
Commercial and industrial loans
Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward]
Balance at beginning of period	4,196	2,648
Originations	4,159	8,372
Sales	(7,703)	(7,159)
Principal payoffs and amortization	(12)	(4)
Balance at end of period	$ 640	$ 3,857

Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward]

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- Definition

Principal payoffs and amortization.

+ References

No definition available.

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

+ Details

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- Definition

The amount of cash paid for the origination of mortgages that are held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

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- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3337-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3461-108585

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