Investment Securities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$ 507,687	$ 345,580
Available-for-sale Securities	513,500	359,866
Available-for-sale Securities, Gross Unrealized Gain	10,155	14,554
Available-for-sale Securities, Gross Unrealized Loss	4,342	268
US Treasury Securities [Member]
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	15,729	1,501
Available-for-sale Securities	15,383	1,502
Available-for-sale Securities, Gross Unrealized Gain		1
Available-for-sale Securities, Gross Unrealized Loss	346	0
US Government-sponsored Enterprises Debt Securities [Member]
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	2,498	996
Available-for-sale Securities	2,500	1,006
Available-for-sale Securities, Gross Unrealized Gain	2	10
Available-for-sale Securities, Gross Unrealized Loss	0	0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	364,826	222,739
Available-for-sale Securities	365,955	229,929
Available-for-sale Securities, Gross Unrealized Gain	4,630	7,375
Available-for-sale Securities, Gross Unrealized Loss	3,501	185
Small Business Administration pools [Member]
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	32,083	34,577
Available-for-sale Securities	32,656	35,498
Available-for-sale Securities, Gross Unrealized Gain	630	928
Available-for-sale Securities, Gross Unrealized Loss	57	7
US States and Political Subdivisions Debt Securities [Member]
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	85,528	82,495
Available-for-sale Securities	89,906	88,603
Available-for-sale Securities, Gross Unrealized Gain	4,722	6,184
Available-for-sale Securities, Gross Unrealized Loss	344	76
Corporate and other securities [Member]
Marketable Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	7,023	3,272
Available-for-sale Securities	7,100	3,328
Available-for-sale Securities, Gross Unrealized Gain	171	56
Available-for-sale Securities, Gross Unrealized Loss	$ 94	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

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- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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