Loans Receivable - Modified TDRs (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract	Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract Contract
Loans Modified as Troubled Debt Restructurings [Abstract]
Outstanding Principal Balance \| $	$ 9,529	$ 11,928	$ 33,880	$ 25,423
Number of contracts modified \| contract	1	1	3	7
Interest and Fee Income, Loans and Leases \| $	$ 46,863	$ 47,647	$ 147,137	$ 142,328
Commercial Portfolio Segment
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	7	19	41	48,000
Outstanding Principal Balance \| $	$ 8,985	$ 9,967	$ 32,763	$ 23,338
Commercial Portfolio Segment \| Commercial and Industrial
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	5	12	32	37,000
Outstanding Principal Balance \| $	$ 1,861	$ 7,217	$ 10,380	$ 17,694
Number of contracts modified \| contract	1	1	3	4
Commercial Portfolio Segment \| Owner Occupied Commercial Real Estate
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	2	5	6	7,000
Outstanding Principal Balance \| $	$ 7,124	$ 2,312	$ 16,710	$ 3,227
Number of contracts modified			0	1
Commercial Portfolio Segment \| Non Owner Occupied Commercial Real Estate
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	0	2	3	4,000
Outstanding Principal Balance \| $	$ 0	$ 438	$ 5,673	$ 2,417
Number of contracts modified \| contract			0	2
Real Estate Construction and Land Development \| One-to-four Family Real Estate Construction
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	0	4	0	4,000
Outstanding Principal Balance \| $	$ 0	$ 1,812	$ 0	$ 1,812
Consumer Portfolio Segment
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	5	9	22	20,000
Outstanding Principal Balance \| $	$ 94	$ 127	$ 487	$ 251
One-to-four Family Real Estate Construction
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	0	1	1	1,000
Outstanding Principal Balance \| $	$ 0	$ 22	$ 180	$ 22
Troubled Debt Restructured Loans
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	13	33	65	73,000
Troubled Debt Restructured Loans \| Modified during the quarter
Loans Modified as Troubled Debt Restructurings [Abstract]
Related Specific Valuation Allowance \| $	$ 3,400	$ 1,600	$ 3,400	$ 1,600
Troubled Debt Restructured Loans \| Finance Receivable Modified Subsequent Default
Loans Modified as Troubled Debt Restructurings [Abstract]
Related Specific Valuation Allowance \| $	$ 13	$ 512	$ 13	$ 512
Troubled Debt Restructured Loans \| Real Estate Construction and Land Development
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	1	4	1	4,000
Outstanding Principal Balance \| $	$ 450	$ 1,812	$ 450	$ 1,812
Troubled Debt Restructured Loans \| Real Estate Construction and Land Development \| Five or More Family Residential and Commercial Properties
Loans Modified as Troubled Debt Restructurings [Abstract]
Number of Contracts \| contract	1	0	1	0
Outstanding Principal Balance \| $	$ 450	$ 0	$ 450	$ 0

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

+ References

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=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
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