Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Fair Value Measurements - Summary of assets and liabilities measured at fair value on recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Available-for-sale securities
Securities available-for-sale, at fair value	$ 139,165	$ 145,698
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	0		$ 0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	0		$ 0
Mortgage-backed securities – agency
Available-for-sale securities
Securities available-for-sale, at fair value	26,057	26,675
CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	113,108	119,023
Quoted Prices In Active Markets For Identical Assets (Level 1)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Significant Other Observable Inputs (Level 2)
Available-for-sale securities
Securities available-for-sale, at fair value	139,165	145,698
Significant Unobservable Inputs (Level 3)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| Quoted Prices In Active Markets For Identical Assets (Level 1)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| Quoted Prices In Active Markets For Identical Assets (Level 1) \| Mortgage-backed securities – agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| Quoted Prices In Active Markets For Identical Assets (Level 1) \| CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| Significant Other Observable Inputs (Level 2)
Available-for-sale securities
Securities available-for-sale, at fair value	139,165	145,698
Recurring \| Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities – agency
Available-for-sale securities
Securities available-for-sale, at fair value	26,057	26,675
Recurring \| Significant Other Observable Inputs (Level 2) \| CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	113,108	119,023
Recurring \| Significant Unobservable Inputs (Level 3)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Mortgage-backed securities – agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Non-recurring
Available-for-sale securities
Assets	$ 0	$ 0