The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Loans - Summary of Allowance for Loan and Lease Losses for Loans Evaluated Individually and Collectively for Impairment (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	$ 1,492		$ 2,377
Collectively evaluated for impairment	341,732		370,212
Total loans	343,224		372,589
Individually evaluated for impairment	31		12
Collectively evaluated for impairment	3,156		3,250
Total allowance for loan losses	3,187	$ 3,426	3,262	$ 3,092	$ 3,103	$ 3,093
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	386		1,165
Collectively evaluated for impairment	230,184		223,175
Total loans	230,570		224,340
Collectively evaluated for impairment	1,445		1,448
Total allowance for loan losses	1,445	1,644	1,448	1,381	1,372	1,369
Residential [Member]
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	1,046		1,176
Collectively evaluated for impairment	75,829		109,005
Total loans	76,875		110,181
Individually evaluated for impairment			6
Collectively evaluated for impairment	1,172		1,244
Total allowance for loan losses	1,172	1,213	1,250	1,249	1,246	1,246
Consumer [Member]
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	60		36
Collectively evaluated for impairment	35,719		38,032
Total loans	35,779		38,068
Individually evaluated for impairment	31		6
Collectively evaluated for impairment	539		558
Total allowance for loan losses	$ 570	$ 569	$ 564	$ 462	$ 485	$ 478