Loans - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Loans held for sale	$ 625,984	$ 387,514
Other Commercial Loans [Member] \| Carolina Financial [Member]
Business combination lease receivable acquired gross outstanding	$ 13,372
Other Commercial Loans [Member] \| Carolina Financial [Member] \| Maximum [Member]
Business combination lease receivable acquired lease term	60 months
Other Commercial Loans [Member] \| Carolina Financial [Member] \| Minimum [Member]
Business combination lease receivable acquired lease term	12 months
Directors and Officers [Member]
Related party loans	$ 35,816	$ 38,558

Amount of acquired direct financing lease receivable from business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472

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- Definition

Term of lessor's direct financing lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Section 45
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