Investment Securities - Narrative (Details) $ in Thousands	Sep. 30, 2020 USD ($) instrument	Dec. 31, 2019 USD ($)
Investments, Debt and Equity Securities [Abstract]
Carrying value of securities pledged as collateral	$ 989,906	$ 503,427
Book value of securities sold under agreements to repurchase	177,543	182,856
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Gross unrealized losses	187	2,211
Held-to-maturity unrealized losses	1,278	545
State and municipal
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Gross unrealized losses	$ 187	807
Number of securities in unrealized loss positions \| instrument	13
Held-to-maturity unrealized losses	$ 1,240	107
Held-to-maturity, number of securities in unrealized loss positions \| instrument	71
U.S. Government-sponsored agency securities
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Gross unrealized losses	$ 0	0
Held-to-maturity unrealized losses	$ 33	37
Held-to-maturity, number of securities in unrealized loss positions \| instrument	2
Foreign investment
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Held-to-maturity unrealized losses	$ 2	0
Held-to-maturity, number of securities in unrealized loss positions \| instrument	1
U.S. Government-sponsored mortgage-backed securities
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Gross unrealized losses	$ 0	1,404
Held-to-maturity unrealized losses	$ 3	$ 401
Held-to-maturity, number of securities in unrealized loss positions \| instrument	1

Schedule of Available for sale Securities and Held to maturity Securities [Line Items]

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- Definition

Securities Pledged as Collateral

+ References

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- Definition

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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