Loans - Internal Risk Ratings (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Grade:
Loan Receivables	$ 970,528	$ 924,503
Pass
Grade:
Loan Receivables	869,244	912,179
Special Mention
Grade:
Loan Receivables	91,097	3,615
Substandard
Grade:
Loan Receivables	10,187	8,709
Residential First Mortgages
Grade:
Loan Receivables	298,539	293,913
Residential First Mortgages | Pass
Grade:
Loan Receivables	292,427	290,322
Residential First Mortgages | Special Mention
Grade:
Loan Receivables	1,886	1,091
Residential First Mortgages | Substandard
Grade:
Loan Receivables	4,226	2,500
Construction, Land and Land Development
Grade:
Loan Receivables	127,417	126,010
Construction, Land and Land Development | Pass
Grade:
Loan Receivables	109,739	123,916
Construction, Land and Land Development | Special Mention
Grade:
Loan Receivables	15,711
Construction, Land and Land Development | Substandard
Grade:
Loan Receivables	1,967	2,094
Commercial Mortgages (Non-Owner Occupied)
Grade:
Loan Receivables	229,488	196,143
Commercial Mortgages (Non-Owner Occupied) | Pass
Grade:
Loan Receivables	187,794	195,584
Commercial Mortgages (Non-Owner Occupied) | Special Mention
Grade:
Loan Receivables	41,134
Commercial Mortgages (Non-Owner Occupied) | Substandard
Grade:
Loan Receivables	560	559
Commercial Mortgages (Owner Occupied)
Grade:
Loan Receivables	75,455	82,829
Commercial Mortgages (Owner Occupied) | Pass
Grade:
Loan Receivables	62,192	81,936
Commercial Mortgages (Owner Occupied) | Special Mention
Grade:
Loan Receivables	12,669	149
Commercial Mortgages (Owner Occupied) | Substandard
Grade:
Loan Receivables	594	744
Residential Revolving and Junior Mortgages
Grade:
Loan Receivables	31,505	31,893
Residential Revolving and Junior Mortgages | Pass
Grade:
Loan Receivables	30,198	31,084
Residential Revolving and Junior Mortgages | Special Mention
Grade:
Loan Receivables	586	86
Residential Revolving and Junior Mortgages | Substandard
Grade:
Loan Receivables	721	723
Commercial and Industrial
Grade:
Loan Receivables	198,278	181,730
Commercial and Industrial | Pass
Grade:
Loan Receivables	177,247	177,608
Commercial and Industrial | Special Mention
Grade:
Loan Receivables	19,111	2,289
Commercial and Industrial | Substandard
Grade:
Loan Receivables	1,920	1,833
Consumer
Grade:
Loan Receivables	9,846	11,985
Consumer | Pass
Grade:
Loan Receivables	9,647	11,729
Consumer | Substandard
Grade:
Loan Receivables	$ 199	$ 256