Loans and Leases - Summary of Financial Effects of Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) Investment	Dec. 31, 2019 USD ($) Investment	Dec. 31, 2018 USD ($) Investment
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment	43	73	22
Pre-Modification Recorded Investment	$ 24,031	$ 35,287	$ 8,663
Post-Modification Recorded Investment	22,590	30,816	6,355
Trouble debt restructuring, charge-off amount	$ 1,441	4,471	$ 2,308
Capitalized interest		$ 3
Commercial Real Estate
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment	1
Pre-Modification Recorded Investment	$ 15,119
Post-Modification Recorded Investment	$ 15,119
Weighted Average Interest Rate, Pre-Modification	8.00%
Weighted Average Interest Rate, Post-Modification	3.50%
Commercial and Industrial
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment	42	72	21
Pre-Modification Recorded Investment	$ 8,912	$ 35,156	$ 7,763
Post-Modification Recorded Investment	$ 7,471	$ 30,685	$ 5,455
Weighted Average Interest Rate, Pre-Modification	2.36%	4.31%	3.25%
Weighted Average Interest Rate, Post-Modification	2.23%	4.37%	3.13%
Trouble debt restructuring, charge-off amount	$ 1,441	$ 4,471	$ 2,308
One-to-Four Family
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment		1
Pre-Modification Recorded Investment		$ 131
Post-Modification Recorded Investment		$ 131
Weighted Average Interest Rate, Pre-Modification		5.50%
Weighted Average Interest Rate, Post-Modification		5.50%
Capitalized interest		$ 3
Acquisition, Development, and Construction
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment			1
Pre-Modification Recorded Investment			$ 900
Post-Modification Recorded Investment			$ 900
Weighted Average Interest Rate, Pre-Modification			4.50%
Weighted Average Interest Rate, Post-Modification			4.50%

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

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

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