Financial Information [Line Items]

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ 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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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LOAN PORTFOLIO - Loan Portfolio Held for Investment (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Financial Information [Line Items]
Loans held for investment	$ 8,716,953		$ 8,850,476	$ 8,877,214
Less: allowance for loan and lease losses	(200,563)	$ (222,035)	(231,843)	$ (230,870)	$ (173,485)	$ (205,603)
Loans held for investment, net	8,516,390		8,618,633
Residential Mortgage [Member]
Financial Information [Line Items]
Loans held for investment	3,207,981		3,290,957
Construction Loans [Member]
Financial Information [Line Items]
Loans held for investment	82,862		111,397
Commercial Real Estate Portfolio Segment [Member]
Financial Information [Line Items]
Loans held for investment	1,506,502		1,614,972
Commercial And Industrial Sector [Member]
Financial Information [Line Items]
Loans held for investment	2,068,256		2,083,253
Commercial Portfolio Segment [Member]
Financial Information [Line Items]
Loans held for investment	3,657,620		3,809,622
Finance Leases [Member]
Financial Information [Line Items]
Loans held for investment	311,180		257,462
Consumer Portfolio Segment [Member]
Financial Information [Line Items]
Loans held for investment	$ 1,540,172		$ 1,492,435