Fair value - Recurring and non recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 13,300	$ 34,400
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	13,275	34,421
IRLC	513	1,552
Financial Liabilities-Recurring Forward sales commitment	842	3,105
Reported Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned		336
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
US Government Agencies	40,157	0
Mortgage-backed securities		0
Subordinated debt	250	0
Loans held for sale		0
IRLC		0
Financial Liabilities-Recurring Forward sales commitment		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
US Government Agencies	1,673	8,142
Mortgage-backed securities	35,816	24,006
Municipals	2,182
Subordinated debt	7,921	8,446
Loans held for sale	13,275	34,421
IRLC	513	1,552
Financial Liabilities-Recurring Forward sales commitment	842	3,105
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
US Government Agencies	0
Mortgage-backed securities	0
Municipals	0
Subordinated debt	550	250
Loans held for sale	0
IRLC	0
Financial Liabilities-Recurring Forward sales commitment	0
Fair Value, Measurements, Recurring [Member] | Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
US Government Agencies	41,830	8,142
Mortgage-backed securities	35,816	24,006
Municipals	2,182
Subordinated debt	8,721	8,696
Loans held for sale	13,275	34,421
IRLC	513	1,552
Financial Liabilities-Recurring Forward sales commitment	$ 842	3,105
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned		0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned		0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned		336
Fair Value, Measurements, Nonrecurring [Member] | Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned		$ 336