Investment Securities - Narrative (Details) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) position	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Securities, Available-for-sale [Line Items]
Loss upon acquisition of interest-only GNMA securities	$ 7,500	$ 7,476	$ 0	$ 0
Unrealized (gain) loss on investment securities		$ 1,299	(1,634)	$ 0
Number of available for sale debt securities in an unrealized loss position (position) \| position		0
Pledged investment securities fair value		$ 20,400	$ 23,000
Interest-only GNMA securities
Debt Securities, Available-for-sale [Line Items]
Loss upon acquisition of interest-only GNMA securities		7,500
Interest-only GNMA securities		$ 16,272

Loss Upon Acquisition of Interest-Only GNMA Securities

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of investments classified as other.

+ References

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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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.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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