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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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	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Available-for-sale securities
Securities available-for-sale, at fair value	$ 122,625	$ 146,419
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	23,997	25,037
CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	98,628	121,382
(Level 1)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
(Level 2)
Available-for-sale securities
Securities available-for-sale, at fair value	122,625	146,419
(Level 3)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| (Level 1)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| (Level 1) \| Mortgage-backed securities - agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| (Level 1) \| CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| (Level 2)
Available-for-sale securities
Securities available-for-sale, at fair value	122,625	146,419
Recurring \| (Level 2) \| Mortgage-backed securities - agency
Available-for-sale securities
Securities available-for-sale, at fair value	23,997	25,037
Recurring \| (Level 2) \| CMO's - agency
Available-for-sale securities
Securities available-for-sale, at fair value	98,628	121,382
Recurring \| (Level 3)
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| (Level 3) \| Mortgage-backed securities - agency
Available-for-sale securities
Securities available-for-sale, at fair value	0	0
Recurring \| (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