Income Taxes - Components of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Allowance for loan losses	$ 1,588	$ 1,629
Other real estate owned	203	226
Pension and post-retirement benefit plans	179	127
Unrealized losses on available-for-sale securities		333
Deferred and share-based compensation plans	317	237
Fair value adjustments on acquired loans and time deposits resulting from the Merger	500	969
Net deferred loan fees	66	53
Other	252	124
Total deferred tax assets	3,105	3,698
Deferred tax liabilities
Depreciation of fixed assets	(556)	(359)
Amortization of goodwill and core deposit intangible asset	(909)	(1,050)
Premium on fixed assets acquired in the Merger	(518)	(553)
Unrealized gains on available-for-sale securities	(116)
Recapture of bad debts experience reserve	(102)	(178)
Other	(85)	(48)
Total deferred tax liabilities	(2,286)	(2,188)
Deferred tax asset, net	$ 819	$ 1,510