Fair Value of Financial Instruments - Assets and Liabilities Carried at Fair Value on a Recurring Basis, Classified Within Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Trust Preferred Securities [Member]
Beginning balance	$ 1,355	$ 1,289	$ 1,332	$ 1,256
Net (loss) gain from fair value adjustment of financial assets	(285)	15	(261)	47
Increase (decrease) in accrued interest receivable	(2)	(1)	(3)
Ending balance	1,068	1,303	1,068	1,303
Junior Subordinated Debentures [Member]
Beginning balance	45,126	42,941	44,384	41,849
Net loss (gain) from fair value adjustment of financial liabilities	(10,334)	543	(7,983)	1,753
(Decrease) increase in accrued interest payable	(61)	(21)	(85)	(11)
Change in unrealized gains included in other comprehensive income	839	(49)	(746)	(177)
Ending balance	35,570	43,414	35,570	43,414
Changes in unrealized gains held at period end	$ 2,223	$ 1,425	$ 2,223	$ 1,425

Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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The increase (decrease) during the reporting period in the amount due from borrowers for interest payments.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.

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