Loans to Officers and Directors - Activity with Respect to Aggregate Loans to Related Parties (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Related Party Transactions [Abstract]
Balance – beginning of year	$ 207,734	$ 257,575
New loans	39,217	32,923
Repayments	(81,556)	(77,692)
Reduction due to change in reportable loans		(5,072)
Balance – end of year	$ 165,395	$ 207,734

Loans and leases receivable related parties reduction due to change in reportable loans.

No definition available.

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Period Type:	duration

- Definition

Loans and Leases Receivable, Related Parties, Repayments

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- 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
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: 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(e))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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