Investment Securities - Summary of Contractual Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities available-for-sale:
Amortized Cost, Within one year	$ 0
Amortized Cost, One to five years	2,200
Amortized Cost, Five to ten years	849
Amortized Cost, Greater than ten years	2,332
Amortized Cost, Mortgage-backed securities and collateralized mortgage obligations	121,054
Amortized Cost	126,435	$ 97,851
Fair Value, Within one year	0
Fair Value, One to five years	2,303
Fair Value, Five to ten years	887
Fair Value, Greater than ten years	2,641
Fair Value, Mortgage-backed securities and collateralized mortgage obligations	123,151
Fair Value	$ 128,982	$ 97,566

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27198-111563

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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