5. Loans, Allowance for Loan Losses and Credit Quality (Details 6)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) integer	Sep. 30, 2018 USD ($) integer	Sep. 30, 2019 USD ($) integer	Sep. 30, 2018 USD ($) integer	Dec. 31, 2018 USD ($) integer
Number of contracts modified as TDRs | integer	2	1	9	8	11
Pre-Modification outstanding recorded investment	$ 309,896	$ 49,108	$ 887,724	$ 947,671	$ 1,438,250
Post-Modification outstanding recorded investment	$ 320,510	$ 50,814	$ 929,557	$ 1,054,280	$ 1,549,009
Commercial and industrial
Number of contracts modified as TDRs | integer	1		3
Pre-Modification outstanding recorded investment	$ 288,912		$ 338,129
Post-Modification outstanding recorded investment	$ 288,912		$ 338,129
Commercial Real Estate
Number of contracts modified as TDRs | integer	0		1		1
Pre-Modification outstanding recorded investment	$ 0		$ 19,265		$ 406,920
Post-Modification outstanding recorded investment	$ 0		$ 21,628		$ 406,920
Residential real estate - 1st lien
Number of contracts modified as TDRs | integer	1	1	5	8	10
Pre-Modification outstanding recorded investment	$ 20,984	$ 49,108	$ 530,330	$ 947,671	$ 1,031,330
Post-Modification outstanding recorded investment	$ 31,598	$ 50,814	$ 569,800	$ 1,054,280	$ 1,142,089